Nanomaterials

14 pages, 3265 KiB

Open AccessEditor’s ChoiceArticle

Graphene/PtSe₂/Ultra-Thin SiO₂/Si Broadband Photodetector with Large Responsivity and Fast Response Time

by Qing-Hai Zhu, Jian Chai, Shi-Yu Wei, Jia-Bao Sun, Yi-Jun Sun, Daisuke Kiriya and Ming-Sheng Xu

Nanomaterials 2025, 15(7), 519; https://doi.org/10.3390/nano15070519 - 29 Mar 2025

Viewed by 334

Abstract

Burgeoning two-dimensional (2D) materials provide more opportunities to overcome the shortcomings of silicon-based photodetectors. However, the inevitable carrier loss in the 2D material/Si heterojunction has seriously hindered further improvement in responsivity and detection speed. Here, we propose a graphene/PtSe₂/ultra-thin SiO₂ [...] Read more.

Burgeoning two-dimensional (2D) materials provide more opportunities to overcome the shortcomings of silicon-based photodetectors. However, the inevitable carrier loss in the 2D material/Si heterojunction has seriously hindered further improvement in responsivity and detection speed. Here, we propose a graphene/PtSe₂/ultra-thin SiO₂/Si photodetector (PD) with multiple optimization mechanisms. Due to the fact that photo-generated carriers can travel in the graphene plane toward the Au electrode, the introduction of a top graphene contact with low sheet resistance provides a carrier collection path in the vertical direction and further restricts the carrier recombination behavior at the lateral grain boundary of PtSe₂ film. The ultra-thin SiO₂ passivation layer reduces the defects at the PtSe₂/Si heterojunction interface. As compared to the counterpart device without the graphene top contact, the responsivity, specific detectivity, and response speed of graphene/PtSe₂/ultra-thin SiO₂/Si PD under 808 nm illumination are improved to 0.572 A/W, 1.50 × 10¹¹ Jones, and 17.3/38.8 µs, respectively. The device can detect broad-spectrum optical signals as measured from 375 nm to 1550 nm under zero bias. The PD line array with 16-pixel units shows good near-infrared imaging ability at room temperature. Our study will provide guiding significance for how to improve the comprehensive properties of PDs based on 2D/Si heterostructure for practical applications. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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12 pages, 4145 KiB

Open AccessEditor’s ChoiceArticle

The Effect of Al₂O₃ Nanoparticles on Hexagonal Boron Nitride Films Resulting from High-Temperature Annealing

by Qiang Li, Kangkang Liu, Ransheng Chen, Wannian Fang, Zhihao Zhang, Youwei Chen, Haifeng Liu, Ziyan Lin, Yuhuai Liu and Tao Wang

Nanomaterials 2025, 15(7), 484; https://doi.org/10.3390/nano15070484 - 24 Mar 2025

Viewed by 238

Abstract

A simple two-step approach was proposed to obtain hBN thin films with high crystalline quality, meaning that the films were initially prepared by using an RF magnetron sputtering technique and subsequently followed by a post-annealing process at a high temperature. In the case [...] Read more.

A simple two-step approach was proposed to obtain hBN thin films with high crystalline quality, meaning that the films were initially prepared by using an RF magnetron sputtering technique and subsequently followed by a post-annealing process at a high temperature. In the case of introducing Al₂O₃ nanoparticles, the effects of annealing temperature from 1000 °C to 1300 °C and annealing time from 0.5 h to 1.5 h on the recrystallization process of the grown hBN films were systematically studied by using XRD and SEM technologies. The introduction of Al₂O₃ impurities during the annealing process successfully reduced the transition temperature of hexagonal phase BN by more than 300 °C. The crystalline quality of hBN films grown by RF magnetron sputtering could be effectively enhanced under annealing at 1100 °C for 1 h. The DUV detectors were prepared using the hBN films before and after annealing, and showed a notable improvement in detector performance by using annealed films. It has significant application value in further enhancing the performance of DUV photodetectors based on high-quality hBN films. Full article

(This article belongs to the Special Issue Trends and Prospects in Nanoscale Thin Films and Coatings)

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22 pages, 11419 KiB

Open AccessEditor’s ChoiceArticle

A Modified Model Dielectric Function for Analyzing Optical Spectra of InGaN Nanofilms on Sapphire Substrates

by Devki N. Talwar, Hao-Hsiung Lin and Jason T. Haraldsen

Nanomaterials 2025, 15(7), 485; https://doi.org/10.3390/nano15070485 - 24 Mar 2025

Viewed by 238

Abstract

Due to a lower InN bandgap

e n e r g y E_{g} ~ 0.7 e V

,

{I n}_{x} {G a}_{1 - x} N / S a p p h i r e

epifilms are considered valuable [...] Read more.

Due to a lower InN bandgap

e n e r g y E_{g} ~ 0.7 e V

,

{I n}_{x} {G a}_{1 - x} N / S a p p h i r e

epifilms are considered valuable in the development of low-dimensional heterostructure-based photonic devices. Adjusting the composition x and thickness d in epitaxially grown films has offered many possibilities of light emission across a wide spectral range, from ultraviolet through visible into near-infrared regions. Optical properties have played important roles in making semiconductor materials useful in electro-optic applications. Despite the efforts to grow

{I n}_{x} {G a}_{1 - x} N

/Sapphire samples, no x- and d-dependent optical studies exist for ultrathin films. Many researchers have used computationally intensive methods to study the electronic band structures

E_{j} (\vec{k}),

and subsequently derive optical properties. By including inter-band transitions at critical points from

E_{j} (\vec{k})

, we have developed a semiempirical approach to comprehend the optical characteristics of InN, GaN and

{I n}_{x} {G a}_{1 - x} N

. Refractive indices of

{I n}_{x} {G a}_{1 - x} N

and sapphire substrate are meticulously integrated into a transfer matrix method to simulate d- and x-dependent reflectivity

R (E)

and transmission

T (E)

spectra of nanostructured

{I n}_{x} {G a}_{1 - x} N / S a p p h i r e

epifilms. Analyses of

R (E)

and

T (E)

have offered accurate x-dependent shifts of energy gaps for

{I n}_{x} {G a}_{1 - x} N

(x = 0.5, 0.7) in excellent agreement with the experimental data. Full article

(This article belongs to the Section Nanocomposite Materials)

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17 pages, 3301 KiB

Open AccessEditor’s ChoiceArticle

Adsorption of Macrolide Antibiotics by Aged Microplastics of Different Sizes: Mechanisms and Effects

by Qi Li, Jingnan Tan, Haichao Sha, Ke Li and Xi Li

Nanomaterials 2025, 15(6), 467; https://doi.org/10.3390/nano15060467 - 19 Mar 2025

Viewed by 259

Abstract

Microplastics (MPs) and antibiotics are widely detected in water bodies. However, the adsorption behavior and mechanism of different particle size polystyrene (PS) MPs on macrolide antibiotics under natural aging remain to be elucidated. In this study, potassium persulfate (K₂S₂O [...] Read more.

Microplastics (MPs) and antibiotics are widely detected in water bodies. However, the adsorption behavior and mechanism of different particle size polystyrene (PS) MPs on macrolide antibiotics under natural aging remain to be elucidated. In this study, potassium persulfate (K₂S₂O₈) was used to simulate the natural aging process of PS MPs. The adsorption behavior and mechanism of different size PS (80 and 400 μm) toward azithromycin (AZI), clarithromycin (CLA), and erythromycin (ERY) were investigated. Results of SEM showed that the surface roughness of aged PS MPs increased with the appearance of cracks, pits, and pores. XPS and FTIR analyses showed enhanced C=O functional groups in the aging process. The adsorption isotherm models revealed that the aging processes enhanced the AZI, CLA, and ERY adsorption tendency, as evidenced by the highest adsorption capacity for aged-80 μm (645, 665, 184 mg/kg) > original-80 μm (412, 420, 120 mg/kg), and aged-400 μm (280, 330, 110 mg/kg) > original-400 μm (197, 308, 100 mg/kg). Kinetic model fitting revealed that the adsorption process occurred in three stages: rapid, slow, and saturation. Adsorption kinetic curves for original and aged PS MPs conformed to the pseudo-second-order kinetic model. In contrast, the adsorption isotherm data fit the Langmuir model, indicating that the process primarily involved uniform monolayer chemical adsorption. Our findings provide insights into the substantial changes in the interactions between PS and macrolide antibiotics with aging processes. Full article

(This article belongs to the Special Issue Gas–Liquid–Solid Interface Characterization and Targeted Regulation)

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9 pages, 5541 KiB

Open AccessEditor’s ChoiceArticle

Uniform Molecular Alignment on Ag-Doped Nickel Oxide Films

by Dong Wook Lee, Tae-Hyun Kim, Young Kwon Kim and Dae-Shik Seo

Nanomaterials 2025, 15(6), 449; https://doi.org/10.3390/nano15060449 - 15 Mar 2025

Viewed by 428

Abstract

This study presents the uniform alignment of liquid crystal (LC) molecules on silver (Ag)-doped nickel oxide (NiO) films. The films were fabricated using a solution brush coating process, with Ag doping concentrations of 0, 10, and 20 wt%. X-ray photoelectron spectroscopy confirmed the [...] Read more.

This study presents the uniform alignment of liquid crystal (LC) molecules on silver (Ag)-doped nickel oxide (NiO) films. The films were fabricated using a solution brush coating process, with Ag doping concentrations of 0, 10, and 20 wt%. X-ray photoelectron spectroscopy confirmed the successful formation of the films, while atomic force microscopy revealed nano/microgroove anisotropic structures, attributed to brush hair movement during coating. X-ray diffraction analysis indicated the films’ amorphous nature. Optical transmittance measurements demonstrated their suitability for electronic display applications. Polarized optical microscopy verified uniform LC molecular alignment and effective optical control. The fabricated LC cells exhibited increased LC polar anchoring energy, improving device stability. The polar anchoring energy increased by 1159.02% after Ag doping. Additionally, reduced residual charge was observed, suggesting minimized image sticking. These findings indicate that Ag-doped NiO films are a promising alternative for LC alignment layers in functional LC systems. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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18 pages, 7168 KiB

Open AccessEditor’s ChoiceArticle

Robust Carbon Nanotube Transistor Ion Sensors with Near-Nernstian Sensitivity for Multi-Ion Detection in Neurological Diseases

by Lidan Yan, Yang Zhang, Zhibiao Zhu, Yuqi Liang and Mengmeng Xiao

Nanomaterials 2025, 15(6), 447; https://doi.org/10.3390/nano15060447 - 15 Mar 2025

Viewed by 486

Abstract

Accurate monitoring of sodium and potassium ions in biological fluids is crucial for diseases related to electrolyte imbalance. Low-dimensional materials such as carbon nanotubes can be used to construct biochemical sensors based on high-performance field effect transistor (FET), but they face the problems [...] Read more.

Accurate monitoring of sodium and potassium ions in biological fluids is crucial for diseases related to electrolyte imbalance. Low-dimensional materials such as carbon nanotubes can be used to construct biochemical sensors based on high-performance field effect transistor (FET), but they face the problems of poor device consistency and difficulty in stable and reliable operation. In this work, we mass-produced carbon nanotube (CNT) floating-gate field-effect transistor devices with high uniformity and consistency through micro-/nanofabrication technology to improve the accuracy and reliability of detection without the need for statistical analysis based on machine learning. By introducing waterproof hafnium oxide gate dielectrics on the CNT FET channel, we not only effectively protect the channel area but also significantly improve the stability of the sensor. We have prepared array sensing technology based on CNT FET that can detect potassium, sodium, calcium, and hydrogen ions in artificial cerebrospinal fluid. The detection concentration range is 10 μM–100 mM and pH 3–pH 9, with a sensitivity close to the Nernst limit, and exhibits selective and long-term stable responses. This could help achieve early diagnosis and real-time monitoring of central nervous system diseases, highlighting the potential of this ion-sensing platform for highly sensitive and stable detection of various neurobiological markers. Full article

(This article belongs to the Special Issue Advanced Low-Dimensional Materials for Sensing Applications)

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18 pages, 7417 KiB

Open AccessEditor’s ChoiceArticle

Densely Stacked CoCu-MOFs Coated with CuAl/LDH Enhance Sulfamethoxazole Degradation in PMS-Activated Systems

by Xin Zhong, Xiaojun Liu, Meihuan Ji and Fubin Jiang

Nanomaterials 2025, 15(6), 432; https://doi.org/10.3390/nano15060432 - 11 Mar 2025

Viewed by 454

Abstract

As the most promising techniques for refractory antibiotic degradation in wastewater management, sulfate radical-based advanced oxidation processes (SR-AOPs) have attracted considerable attention. However, systematic studies on potassium peroxymonosulfate (PMS) activation by MOF-derived metal oxides coated with LDH materials are still lacking. In this [...] Read more.

As the most promising techniques for refractory antibiotic degradation in wastewater management, sulfate radical-based advanced oxidation processes (SR-AOPs) have attracted considerable attention. However, systematic studies on potassium peroxymonosulfate (PMS) activation by MOF-derived metal oxides coated with LDH materials are still lacking. In this work, a series of catalysts consisting of CoCu-MOFs coated with CuAl/LDH were synthesized for PMS activation in the removal of sulfamethoxazole (SMX). As expected, CoCu-MOFs coated with CuAl/LDH catalyst showed high SMX removal and stability in PMS activation. In the CoCu/LDH/PMS reaction, the SMX removal was nearly 100% after 60 min, and the mineralization reached 53.7%. The catalyst showed excellent catalytic stability and low metal leaching concentrations (Co: 0.013 mg/L, Cu: 0.313 mg/L), as detected by ICP. Sulfate radicals and hydroxyl radicals were identified as the dominant reactive species in the CoCu/LDH/PMS system. Moreover, the presence of ¹O₂ in the process revealed the coupling of non-radical and radical processes. The XPS results showed that the layered structure of CoCu/LDH promoted the recycling of metal ions (high and low valence), which facilitated heterogeneous PMS activation. The effects of different reaction conditions and reuse cycles were also determined. The SMX oxidation pathways were proposed based on the intermediates identified by LC/MS. The high activity and stability of CoCu/LDH provide a new mechanistic understanding of PMS activation catalysts and their potential utilization in practical wastewater treatment. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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15 pages, 2527 KiB

Open AccessEditor’s ChoiceArticle

The Chemical Deformation of a Thermally Cured Polyimide Film Surface into Neutral 1,2,4,5-Benzentetracarbonyliron and 4,4′-Oxydianiline to Remarkably Enhance the Chemical–Mechanical Planarization Polishing Rate

by Man-Hyup Han, Hyun-Sung Koh, Il-Haeng Heo, Myung-Hoe Kim, Pil-Su Kim, Min-Uk Jeon, Min-Ji Kim, Woo-Hyun Jin, Kyoo-Chul Cho, Jinsub Park and Jea-Gun Park

Nanomaterials 2025, 15(6), 425; https://doi.org/10.3390/nano15060425 - 10 Mar 2025

Viewed by 742

Abstract

The rapid advancement of 3D packaging technology has emerged as a key solution to overcome the scaling-down limitation of advanced memory and logic devices. Redistribution layer (RDL) fabrication, a critical process in 3D packaging, requires the use of polyimide (PI) films with thicknesses [...] Read more.

The rapid advancement of 3D packaging technology has emerged as a key solution to overcome the scaling-down limitation of advanced memory and logic devices. Redistribution layer (RDL) fabrication, a critical process in 3D packaging, requires the use of polyimide (PI) films with thicknesses in the micrometer range. However, these polyimide films present surface topography variations in the range of hundreds of nanometers, necessitating chemical–mechanical planarization (CMP) to achieve nanometer-level surface flatness. Polyimide films, composed of copolymers of pyromellitimide and diphenyl ether, possess strong covalent bonds such as C–C, C–O, C=O, and C–N, leading to inherently low polishing rates during CMP. To address this challenge, the introduction of Fe(NO₃)₃ into CMP slurries has been proposed as a polishing rate accelerator. During CMP, this Fe(NO₃)₃ deformed the surface of a polyimide film into strongly positively charged 1,2,4,5-benzenetetracarbonyliron and weakly negatively charged 4,4′-oxydianiline (ODA). The chemically dominant polishing rate enhanced with the concentration of the Fe(NO₃)₃ due to accelerated surface interactions. However, higher Fe(NO₃)₃ concentrations reduce the attractive electrostatic force between the positively charged wet ceria abrasives and the negatively charged deformed surface of the polyimide film, thereby decreasing the mechanically dominant polishing rate. A comprehensive investigation of the chemical and mechanical polishing rate dynamics revealed that the optimal Fe(NO₃)₃ concentration to achieve the maximum polyimide film removal rate was 0.05 wt%. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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14 pages, 2249 KiB

Open AccessEditor’s ChoiceArticle

Comparative Assessment of the Impacts of Wildland–Urban Interface Fire Ash on Growth of the Diatom Thalassiosira weissflogii

by Talal Alshehri, Amar Yasser Jassim, Bo Cai, Tammi L. Richardson and Mohammed Baalousha

Nanomaterials 2025, 15(6), 422; https://doi.org/10.3390/nano15060422 - 9 Mar 2025

Viewed by 509

Abstract

Fires at the wildland–urban interface (WUI) result in the release of ash into the atmosphere that can be transported for long distances and deposited on land and in oceans. Wildfire ash has the potential to increase phytoplankton biomass in the open ocean by [...] Read more.

Fires at the wildland–urban interface (WUI) result in the release of ash into the atmosphere that can be transported for long distances and deposited on land and in oceans. Wildfire ash has the potential to increase phytoplankton biomass in the open ocean by providing both major nutrients and trace metals. However, fires that originate at the WUI contain potentially toxic concentrations of metals such as Ti, Cr, Cu, Pb, and Zn, especially in coastal oceans close to WUI fires, where ash deposition rates are high. Here, we investigated the impact of fire ash from different sources originating from vegetation, structures, and vehicles on growth of the diatom Thalassiosira weissflogii (T. weissflogii). The diatom was exposed to ash suspensions containing equimolar concentrations of 10 and 50 µM Fe. The concentration of potentially toxic metals (e.g., Ti, Cu, and Zn) in the exposure suspensions decreased following the order vehicle ash suspension > structural ash suspension > vegetation ash suspension. Growth rates (GR) of T. weissflogii were between 0.44 d⁻¹ and 0.52 d⁻¹ in the controls, and varied with ash types, following the order vegetation (GR = 0.40 d⁻¹ to 0.48 d⁻¹) > vehicle (GR = 0.06 d⁻¹ to 0.46 d⁻¹) > structure (GR = 0.02 d⁻¹ to 0.31 d⁻¹) ash. Two ash samples (A 131 and A136) completely inhibited the growth of T. weissflogii, possibly due to high Ti, Cu, and Zn concentrations in the form of (nano)particles. Overall, this study showed that structural and vehicle ash, with high concentrations of potentially toxic metals, significantly suppress the growth of T. weissflogii, whereas vegetation ash with high concentrations of Fe and Mn but low concentrations of potentially toxic metals had no significant beneficial or suppressive effect. High concentrations of the metals Ti, Cu, and Zn in the form of nano(particles) in structural and vehicle ash are possible sources of toxicity to diatom growth. This study provides valuable insights into the potential impacts of WUI fires on aquatic ecosystems and can inform management strategies aimed at reducing these impacts. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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18 pages, 5239 KiB

Open AccessEditor’s ChoiceArticle

A Facile Two-Step High-Throughput Screening Strategy of Advanced MOFs for Separating Argon from Air

by Xiaoyi Xu, Bingru Xin, Zhongde Dai, Chong Liu, Li Zhou, Xu Ji and Yiyang Dai

Nanomaterials 2025, 15(6), 412; https://doi.org/10.3390/nano15060412 - 7 Mar 2025

Viewed by 466

Abstract

Metal–organic frameworks (MOFs) based on the pressure swing adsorption (PSA) process show great promise in separating argon from air. As research burgeons, the number of MOFs has grown exponentially, rendering the experimental identification of materials with significant gas separation potential impractical. This study [...] Read more.

Metal–organic frameworks (MOFs) based on the pressure swing adsorption (PSA) process show great promise in separating argon from air. As research burgeons, the number of MOFs has grown exponentially, rendering the experimental identification of materials with significant gas separation potential impractical. This study introduced a high-throughput screening through a two-step strategy based on structure–property relationships, which leveraged Grand Canonical Monte Carlo (GCMC) simulations, to swiftly and precisely identify high-performance MOF adsorbents capable of separating argon from air among a vast array of MOFs. Compared to traditional approaches for material development and screening, this method significantly reduced both experimental and computational resource requirements. This research pre-screened 12,020 experimental MOFs from a computationally ready experimental MOF (CoRE MOF) database down to 7328 and then selected 4083 promising candidates through structure–performance correlation. These MOFs underwent GCMC simulation assessments, showing superior adsorption performance to traditional molecular sieves. In addition, an in-depth discussion was conducted on the structural characteristics and metal atoms among the best-performing MOFs, as well as the effects of temperature, pressure, and real gas conditions on their adsorption properties. This work provides a new direction for synthesizing next-generation MOFs for efficient argon separation in labs, contributing to energy conservation and consumption reduction in the production of high-purity argon gas. Full article

(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)

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18 pages, 6287 KiB

Open AccessEditor’s ChoiceArticle

Folic Acid-Conjugated Magnetic Oleoyl-Chitosan Nanoparticles for Controlled Release of Doxorubicin in Cancer Therapy

by Banendu Sunder Dash, Yi-Chian Lai and Jyh-Ping Chen

Nanomaterials 2025, 15(6), 415; https://doi.org/10.3390/nano15060415 - 7 Mar 2025

Cited by 1 | Viewed by 823

Abstract

To develop an efficient drug delivery system, we co-entrapped superparamagnetic Fe₃O₄ and the chemotherapeutic drug doxorubicin (DOX) in oleoyl-chitosan (OC) to prepare DOX-entrapped magnetic OC (DOX-MOC) nanoparticles (NPs) through ionic gelation of OC with sodium tripolyphosphate (TPP). The NPs provide [...] Read more.

To develop an efficient drug delivery system, we co-entrapped superparamagnetic Fe₃O₄ and the chemotherapeutic drug doxorubicin (DOX) in oleoyl-chitosan (OC) to prepare DOX-entrapped magnetic OC (DOX-MOC) nanoparticles (NPs) through ionic gelation of OC with sodium tripolyphosphate (TPP). The NPs provide magnetically targeted delivery of DOX in cancer therapy. Using folic acid (FA)-grafted OC, FA-conjugated DOX-entrapped magnetic OC (FA-DOX-MOC) NPs were prepared similarly for FA-mediated active targeting of cancer cells with overexpressed folate receptors. Considering DOX loading and release, the best conditions for preparing DOX-MOC NPs were an OC:TPP mass ratio = 1:4 and OC concentration = 0.2%. These spherical NPs had a particle size of ~250 nm, 87.9% Fe₃O₄ content, 53.1 emu/g saturation magnetization, 83.1% drug encapsulation efficacy, and 2.81% drug loading efficiency. FA did not significantly change the physico-chemical characteristics of FA-DOX-MOC compared to DOX-MOC, and both NPs showed pH-dependent drug release behaviors, with much faster release of DOX at acidic pH values found in endosomes. However, FA could enhance the intracellular uptake of the NPs and DOX accumulation in the nucleus. This active targeting effect led to significantly higher cytotoxicity towards U87 cancer cells. These results suggest that FA-DOX-MOC NPs can efficiently deliver DOX for controlled drug release in cancer therapy. Full article

(This article belongs to the Section Biology and Medicines)

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10 pages, 4851 KiB

Open AccessEditor’s ChoiceArticle

Room-Temperature Synthesis of Carbon Nanochains via the Wurtz Reaction

by Juxiang Pu, Yongqing Gong, Menghao Yang and Mali Zhao

Nanomaterials 2025, 15(5), 407; https://doi.org/10.3390/nano15050407 - 6 Mar 2025

Viewed by 542

Abstract

In the field of surface synthesis, various reactions driven by the catalytic effect of metal substrates, particularly the Ullmann reaction, have been thoroughly investigated. The Wurtz reaction facilitates the coupling of alkyl halides through the removal of halogen atoms with a low energy [...] Read more.

In the field of surface synthesis, various reactions driven by the catalytic effect of metal substrates, particularly the Ullmann reaction, have been thoroughly investigated. The Wurtz reaction facilitates the coupling of alkyl halides through the removal of halogen atoms with a low energy barrier on the surface; however, the preparation of novel carbon nanostructures via the Wurtz reaction has been scarcely reported. Here, we report the successful synthesis of ethyl-bridged binaphthyl molecular chains on Ag(111) at room temperature via the Wurtz reaction. However, this structure was not obtained through low-temperature deposition followed by annealing even above room temperature. High-resolution scanning tunneling microscopy combined with density functional theory calculations reveal that the rate-limiting step of C–C homocoupling exhibits a low-energy barrier, facilitating the room-temperature synthesis of carbon nanochain structures. Moreover, the stereochemical configuration of adsorbed molecules hinders the activation of the C–X (X = Br) bond away from the metal surface and, therefore, critically influences the reaction pathways and final products. This work advances the understanding of surface-mediated reactions involving precursor molecules with stereochemical structures. Moreover, it provides an optimized approach for synthesizing novel carbon nanostructures under mild conditions. Full article

(This article belongs to the Special Issue Functionalized Nanostructures on Surfaces and at Interfaces)

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14 pages, 4821 KiB

Open AccessEditor’s ChoiceArticle

Controllable Hydrothermal Synthesis of 1D β-Ga₂O₃ for Solar-Blind Ultraviolet Photodetection

by Lingfeng Mao, Xiaoxuan Wang, Chaoyang Huang, Yi Ma, Feifei Qin, Wendong Lu, Gangyi Zhu, Zengliang Shi, Qiannan Cui and Chunxiang Xu

Nanomaterials 2025, 15(5), 402; https://doi.org/10.3390/nano15050402 - 6 Mar 2025

Viewed by 543

Abstract

Gallium oxide (Ga₂O₃), an ultrawide bandgap semiconductor, is an ideal material for solar-blind photodetectors, but challenges such as low responsivity and response speed persist. In this paper, one-dimensional (1D) Ga₂O₃ nanorods were designed to achieve high [...] Read more.

Gallium oxide (Ga₂O₃), an ultrawide bandgap semiconductor, is an ideal material for solar-blind photodetectors, but challenges such as low responsivity and response speed persist. In this paper, one-dimensional (1D) Ga₂O₃ nanorods were designed to achieve high photodetection performance due to their effective light absorption and light field confinement. Through modulating source concentration, pH value, temperature, and reaction time, 1D β-Ga₂O₃ nanorods were controllably fabricated using a cost-effective hydrothermal method, followed by post-annealing. The nanorods had a diameter of ~500 nm, length from 0.5 to 3 μm, and structure from nanorods to spindles, indicating that different β-Ga₂O₃ nanorods can be utilized controllably through tuning reaction parameters. The 1D β-Ga₂O₃ nanorods with a high length-to-diameter ratio were chosen to construct metal-semiconductor-metal type photodetectors. These devices exhibited a high responsivity of 8.0 × 10⁻⁴ A/W and detectivity of 4.58 × 10⁹ Jones under 254 nm light irradiation. The findings highlighted the potential of 1D Ga₂O₃ nanostructures for high-performance solar-blind ultraviolet photodetectors, paving the way for future integrable deep ultraviolet optoelectronic devices. Full article

(This article belongs to the Special Issue Advanced Nanomaterials and Energetic Application: Experiment and Simulation)

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15 pages, 9197 KiB

Open AccessEditor’s ChoiceArticle

Fluorescent Silver Nanoclusters Associated with Double-Stranded Poly(dGdC) DNA

by Zakhar Reveguk, Roberto Improta, Lara Martínez-Fernández, Ruslan Ramazanov, Shachar Richter and Alexander Kotlyar

Nanomaterials 2025, 15(5), 397; https://doi.org/10.3390/nano15050397 - 5 Mar 2025

Viewed by 603

Abstract

Here, we demonstrate through AFM imaging and CD spectroscopy that the binding of silver ions (Ag⁺) to poly(dGdC), a double-stranded (ds) DNA composed of two identical repeating strands, at a stoichiometry of one Ag⁺ per GC base pair induces a [...] Read more.

Here, we demonstrate through AFM imaging and CD spectroscopy that the binding of silver ions (Ag⁺) to poly(dGdC), a double-stranded (ds) DNA composed of two identical repeating strands, at a stoichiometry of one Ag⁺ per GC base pair induces a one-base shift of one strand relative to the other. This results in a ds nucleic acid-Ag⁺ conjugate consisting of alternating CC and GG base pairs coordinated by silver ions. The proposed organization of the conjugate is supported by the results of our Quantum Mechanical (QM) and Molecular Mechanics (MMs) calculations. The reduction of Ag⁺ ions followed by the partial oxidation of silver atoms yields a highly fluorescent conjugate emitting at 720 nm. This fluorescent behavior in conjugates of long, repetitive ds DNA (thousands of base pairs) with silver has never been demonstrated before. We propose that the poly(dGdC)–Ag conjugate functions as a dynamic system, comprising various small clusters embedded within the DNA and interacting with one another through energy transfer. This hypothesis is supported by the results of our QM and MMs calculations. Additionally, these DNA–silver conjugates, comprising silver nanoclusters, may possess conductive properties, making them potential candidates for use as nanowires in nanodevices and nanosensors. Full article

(This article belongs to the Section Biology and Medicines)

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21 pages, 4584 KiB

Open AccessEditor’s ChoiceArticle

Charging and Aggregation of Nano-Clay Na-Montmorillonite in the Presence of Ciprofloxacin

by Chuanzi Zeng and Motoyoshi Kobayashi

Nanomaterials 2025, 15(5), 389; https://doi.org/10.3390/nano15050389 - 3 Mar 2025

Viewed by 620

Abstract

The transport and fate of antibiotics are significantly influenced by co-existing colloidal and nanosized substances, such as clay particles. Montmorillonite, a common clay mineral with a thin nano-sheet-like structure, enhances antibiotic (e.g., ciprofloxacin) mobility due to its strong adsorption properties. Nevertheless, little is [...] Read more.

The transport and fate of antibiotics are significantly influenced by co-existing colloidal and nanosized substances, such as clay particles. Montmorillonite, a common clay mineral with a thin nano-sheet-like structure, enhances antibiotic (e.g., ciprofloxacin) mobility due to its strong adsorption properties. Nevertheless, little is known about how ciprofloxacin systematically influences the charging and aggregation properties of montmorillonite. This study examines the effect of ciprofloxacin on the electrophoretic mobility and hydrodynamic diameter of Na-montmorillonite under varying pH levels and NaCl concentrations. Results show ciprofloxacin promotes aggregation and alters the surface net charge of Na-montmorillonite at acidic to neutral pH, where ciprofloxacin is positively charged. At higher pH levels, where ciprofloxacin is negatively charged, no significant effects are observed. The observed aggregation behaviors align with predictions based on the Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. Specifically, the slow aggregation regime, the fast aggregation regime, and the critical coagulation concentration are identified. The relationship between critical coagulation ionic strength and electrokinetic surface charge density is well explained by the DLVO theory with the Debye–Hückel approximations. Additionally, non-DLVO interactions are inferred. At low NaCl and ciprofloxacin concentrations, minimal changes in aggregation and surface charge suggest dispersed montmorillonite may facilitate ciprofloxacin transport, raising environmental concerns. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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11 pages, 5067 KiB

Open AccessEditor’s ChoiceArticle

Formation of Homogeneous Nanostructure via Interference of Square Flattop Femtosecond Laser Pulses

by Takemasa Sumimoto and Godai Miyaji

Nanomaterials 2025, 15(5), 355; https://doi.org/10.3390/nano15050355 - 25 Feb 2025

Viewed by 674

Abstract

We report on the formation of homogeneous nanostructures using a two-step ablation process with square flattop beams of femtosecond (fs) laser pulses. The Gaussian beam output from a ytterbium fs laser system was converted to a square flattop beam by a refractive beam [...] Read more.

We report on the formation of homogeneous nanostructures using a two-step ablation process with square flattop beams of femtosecond (fs) laser pulses. The Gaussian beam output from a ytterbium fs laser system was converted to a square flattop beam by a refractive beam shaper and a square mask. This beam was split into two with a diffraction optical element, and then the downsized beams were spatially and temporally superimposed on a titanium surface. In the first step, the interference fringes of these two beams formed grooves with a period of 1.9 µm through ablation. Next, the surface was irradiated at normal incidence by a single beam to form a homogeneous line-like nanostructure with a period of 490 nm in a 53 μm square area. This nanostructure had a constant period and was formed over 95% of the laser-processed area, indicating that the ratio between the nanostructure and modification area was over six times larger than that for a Gaussian beam. Full article

(This article belongs to the Special Issue Laser-Based Nano Fabrication and Nano Lithography: Second Edition)

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27 pages, 8066 KiB

Open AccessEditor’s ChoiceArticle

Tetrahedrite Nanocomposites for High Performance Thermoelectrics

by Rodrigo Coelho, Duarte Moço, Ana I. de Sá, Paulo P. da Luz, Filipe Neves, Maria de Fátima Cerqueira, Elsa B. Lopes, Francisco P. Brito, Panagiotis Mangelis, Theodora Kyratsi and António P. Gonçalves

Nanomaterials 2025, 15(5), 351; https://doi.org/10.3390/nano15050351 - 24 Feb 2025

Viewed by 493

Abstract

Thermoelectric (TE) materials offer a promising solution to reduce green gas emissions, decrease energy consumption, and improve energy management due to their ability to directly convert heat into electricity and vice versa. Despite their potential, integrating new TE materials into bulk TE devices [...] Read more.

Thermoelectric (TE) materials offer a promising solution to reduce green gas emissions, decrease energy consumption, and improve energy management due to their ability to directly convert heat into electricity and vice versa. Despite their potential, integrating new TE materials into bulk TE devices remains a challenge. To change this paradigm, the preparation of highly efficient tetrahedrite nanocomposites is proposed. Tetrahedrites were first prepared by solid state reaction, followed by the addition of MoS₂ nanoparticles (NPs) and hot-pressing at 848 K with 56 MPa for a duration of 90 min to obtain nanocomposites. The materials were characterized by XRD, SEM-EDS, and Raman spectroscopy to evaluate the composites’ matrix and NP distribution. To complement the results, lattice thermal conductivity and the weighted mobility were evaluated. The NPs’ addition to the tetrahedrites resulted in an increase of 36% of the maximum figure of merit (

z T

) comparatively with the base material. This increase is explained by the reduction of the material’s lattice thermal conductivity while maintaining its mobility. Such results highlight the potential of nanocomposites to contribute to the development of a new generation of TE devices based on more affordable and efficient materials. Full article

(This article belongs to the Special Issue Nanoscale Thermoelectric Materials: Advanced Synthesis and Characterisation Approaches)

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17 pages, 5843 KiB

Open AccessEditor’s ChoiceArticle

An In Situ Characterisation Method for 3-D Electrospun Foams

by Kyriakos Almpanidis, Chloe J. Howard and Vlad Stolojan

Nanomaterials 2025, 15(5), 339; https://doi.org/10.3390/nano15050339 - 22 Feb 2025

Viewed by 788

Abstract

Three-dimensional electrospun foams are emerging in a diversity of applications. However, their characterisation involves procedures to calculate fibre diameter and porosity, which take considerable time. Hence, in this paper, an in situ characterisation method is presented based on signal features of the grounding [...] Read more.

Three-dimensional electrospun foams are emerging in a diversity of applications. However, their characterisation involves procedures to calculate fibre diameter and porosity, which take considerable time. Hence, in this paper, an in situ characterisation method is presented based on signal features of the grounding voltage. These features are combined into the in situ evaluation parameter S_r for each run r. The L9 Taguchi method was utilised to minimise the total number of experiments. Moreover, to prove the accuracy of this method, the traditional post-fabrication analysis was conducted, and the post-fabrication evaluation parameter was retrieved Q_r for each run r. The analysis shows that both parameters detected the same experiment run as the optimal one (with an adjusted R² = 0.84) for polystyrene electrospun foams for two solution concentrations: 15%wv (run 3 with mean S₃ = 54.49 and mean Q₃ = 0.248) and 20%wv (mean S₅ = 2.49 and Q₅ = 0.248), respectively. Also, the statistical analysis shows low standard deviations for the optimal and near-optimal runs, proving the method’s repeatability. Furthermore, a theoretical explanation is provided for selecting signal features based on the Maxwellian equivalent circuit approach for the electrospun jet. Finally, this fast in situ evaluation method can replace the post-fabrication time-consuming one. It can be used as a fundamental step for an intelligent artificial intelligence tool that predicts optimal foam formation. Full article

(This article belongs to the Section Nanofabrication and Nanomanufacturing)

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17 pages, 3109 KiB

Open AccessEditor’s ChoiceArticle

Surface Grafting of Graphene Flakes with Fluorescent Dyes: A Tailored Functionalization Approach

by Ylea Vlamidis, Carmela Marinelli, Aldo Moscardini, Paolo Faraci, Stefan Heun and Stefano Veronesi

Nanomaterials 2025, 15(5), 329; https://doi.org/10.3390/nano15050329 - 20 Feb 2025

Viewed by 520

Abstract

The controlled functionalization of graphene is critical for tuning and enhancing its properties, thereby expanding its potential applications. Covalent functionalization offers a deeper tuning of the geometric and electronic structure of graphene compared to non-covalent methods; however, the existing techniques involve side reactions [...] Read more.

The controlled functionalization of graphene is critical for tuning and enhancing its properties, thereby expanding its potential applications. Covalent functionalization offers a deeper tuning of the geometric and electronic structure of graphene compared to non-covalent methods; however, the existing techniques involve side reactions and spatially uncontrolled functionalization, pushing research toward more selective and controlled methods. A promising approach is 1,3-dipolar cycloaddition, successfully utilized with carbon nanotubes. In the present work, this method has been extended to graphene flakes with low defect concentration. A key innovation is the use of a custom-synthesized ylide with a protected amine group (Boc), facilitating subsequent attachment of functional molecules. Indeed, after Boc cleavage, fluorescent dyes (Atto 425, 465, and 633) were covalently linked via NHS ester derivatization. This approach represents a highly selective method of minimizing structural damage. Successful functionalization was demonstrated by Raman spectroscopy, photoluminescence spectroscopy, and confocal microscopy, confirming the effectiveness of the method. This novel approach offers a versatile platform, enabling its use in biological imaging, sensing, and advanced nanodevices. The method paves the way for the development of sensors and devices capable of anchoring a wide range of molecules, including quantum dots and nanoparticles. Therefore, it represents a significant advancement in graphene-based technologies. Full article

(This article belongs to the Special Issue Graphene and Other 2D Layer-Based Nanomaterials for Energy and Sensing Applications)

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20 pages, 6454 KiB

Open AccessEditor’s ChoiceArticle

Variation in Nanocrystalline Phase Content on Mechanical Properties and Wear Resistance of FeCrMoWBRE Amorphous/Nanocrystalline Coating Deposited by High-Velocity Arc Spraying

by Hao Du, Wei Xin, Bo Wang, Ji’an Feng, Xingchuan Xia, Yujiang Wang and Shicheng Wei

Nanomaterials 2025, 15(4), 305; https://doi.org/10.3390/nano15040305 - 17 Feb 2025

Viewed by 480

Abstract

The incorporation of a homogeneously distributed nanocrystalline phase in Fe-based amorphous coatings is widely acknowledged to enhance wear resistance across various applications. In this study, FeCrMoWBRE amorphous/nanocrystalline composite coatings were fabricated on 45# steel substrates using high-velocity arc spraying (HVAS). The coatings were [...] Read more.

The incorporation of a homogeneously distributed nanocrystalline phase in Fe-based amorphous coatings is widely acknowledged to enhance wear resistance across various applications. In this study, FeCrMoWBRE amorphous/nanocrystalline composite coatings were fabricated on 45# steel substrates using high-velocity arc spraying (HVAS). The coatings were produced under varying spraying voltages, currents, and distances, following the Taguchi experimental design methodology. The microstructure, mechanical properties, and wear resistance of the coatings were systematically analyzed, with a particular focus on the relationship between nanocrystalline/amorphous phase content and key performance metrics, including microhardness, adhesive strength, and wear rate. A positive correlation was observed between the nanocrystalline phase content and both mechanical properties and wear resistance. The coating with optimized nanocrystalline phase content of 21.4% exhibits the lowest wear rate of 1.39 × 10⁻⁷ mm³·N⁻¹·m⁻¹ under a 100 N load and oil lubrication. These findings underscore the critical role of controlling the nanocrystalline phase content in Fe-based amorphous/nanocrystalline composite coatings to maximize wear resistance under oil-lubricated conditions. Full article

(This article belongs to the Special Issue Nano Surface Engineering: 2nd Edition)

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11 pages, 2887 KiB

Open AccessEditor’s ChoiceArticle

β-Ga₂O₃ Thin Films via an Inorganic Sol–Gel Spin Coating: Preparation and Characterization

by Hai Zhang, Dingyuan Niu, Junbiao Yang, Xiaoyang Zhang, Jun Zhu and Wencai Li

Nanomaterials 2025, 15(4), 277; https://doi.org/10.3390/nano15040277 - 12 Feb 2025

Viewed by 754

Abstract

β-Ga₂O₃ holds significant promise for use in ultraviolet (UV) detectors and high-power devices due to its ultra-wide bandgap. However, the cost-effective preparation of large-area thin films remains challenging. In this study, β-Ga₂O₃ thin films are prepared using [...] Read more.

β-Ga₂O₃ holds significant promise for use in ultraviolet (UV) detectors and high-power devices due to its ultra-wide bandgap. However, the cost-effective preparation of large-area thin films remains challenging. In this study, β-Ga₂O₃ thin films are prepared using an inorganic solution reaction spin-coating method followed by post-annealing. The structures, surface morphologies, and optical properties of the films are then characterized using X-ray diffraction, scanning electron microscopy, and ultraviolet–visible spectrophotometry. A low-cost Ga metal was used to produce NH₄Ga(SO₄)₂, which was then converted into a precursor solution and spin-coated onto sapphire and quartz substrates. Ten cycles of spin coating produced smoother films, although higher annealing temperatures induced more cracks. The films on the (0001) sapphire subjected to spin-coating and preheating processes that were repeated for ten cycles, followed by annealing at 800 °C, had a preferred orientation in the [–201] direction. All the films showed high transmittances of 85% in ultraviolet–visible light with wavelengths above 400 nm. The films on the (0001) sapphire substrate that were annealed at 800 °C and 1000 °C exhibited bandgaps of 4.8 and 4.98 eV, respectively. The sapphire substrates demonstrated a superior compatibility for high-quality Ga₂O₃ film fabrication compared to quartz. This method offers a cost-effective and efficient approach for producing high-quality β-Ga₂O₃ films on high-temperature-resistant substrates with promising potential for optoelectronic applications. Full article

(This article belongs to the Special Issue Synthesis and Properties of Metal Oxide Thin Films)

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30 pages, 10965 KiB

Open AccessEditor’s ChoiceReview

Computational Modeling of Properties of Quantum Dots and Nanostructures: From First Principles to Artificial Intelligence (A Review)

by Grzegorz Matyszczak, Krzysztof Krawczyk and Albert Yedzikhanau

Nanomaterials 2025, 15(4), 272; https://doi.org/10.3390/nano15040272 - 11 Feb 2025

Viewed by 826

Abstract

Nanomaterials, including quantum dots, have gained more and more attention in the past few decades due to their extraordinary properties that make them useful for many applications, ranging from catalysis, energy generation and storage, biotechnology, and medicine to quantum informatics. Mathematical descriptions of [...] Read more.

Nanomaterials, including quantum dots, have gained more and more attention in the past few decades due to their extraordinary properties that make them useful for many applications, ranging from catalysis, energy generation and storage, biotechnology, and medicine to quantum informatics. Mathematical descriptions of the phenomena in which nanostructures are involved are of great demand because they may be utilized for the purpose of controlling these phenomena (e.g., the growth of nanostructures with certain sizes, shapes, and other properties). Such models may be of distinct nature, including calculations from first principles, ordinary and partial differential equations, and machine learning models (including artificial intelligence) as well. The aim of this article is to review the most important and useful computational and mathematical approaches for the description and control of processes involving nanostructures. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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26 pages, 2988 KiB

Open AccessEditor’s ChoiceArticle

Sustainable Bacterial Cellulose Production Using Low-Cost Fruit Wastewater Feedstocks

by Cláudia Mouro, Arlindo Gomes, Ana P. Gomes and Isabel C. Gouveia

Nanomaterials 2025, 15(4), 271; https://doi.org/10.3390/nano15040271 - 11 Feb 2025

Viewed by 661

Abstract

Bacterial cellulose (BC) is a versatile biopolymer prized for its remarkable water absorption, nanoscale fiber architecture, mechanical robustness, and biocompatibility, making it suitable for diverse applications. Despite its potential, the high cost of conventional fermentation media limits BC’s scalability and wider commercial use. [...] Read more.

Bacterial cellulose (BC) is a versatile biopolymer prized for its remarkable water absorption, nanoscale fiber architecture, mechanical robustness, and biocompatibility, making it suitable for diverse applications. Despite its potential, the high cost of conventional fermentation media limits BC’s scalability and wider commercial use. This study investigates an economical solution by utilizing fractions from fruit processing wastewater, refined through sequential membrane fractionation, as a supplement to commercial HS medium for BC production. BC films were thoroughly characterized using Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and assessments of mechanical properties and water holding capacity (WHC). FTIR confirmed the BC structure, while TEM validated its nanofibrillar 3D network. XRD analysis revealed a slight increasing trend in crystallinity with the addition of wastewater fractions, and DSC revealed a slight increase in thermal stability for F#6. Adding these fractions notably improved the BC films’ tensile strength, Young’s modulus, and WHC. Overall, the results underscore that fruit processing wastewater fractions can serve as a cost-efficient, eco-friendly alternative to traditional fermentation media. This approach supports circular economy principles by lowering reliance on intensive wastewater treatments, promoting waste valorization, and advancing sustainable production methods for high-value biopolymers. Full article

(This article belongs to the Special Issue Theoretical and Computational Study and Modelling on Novel Nanostructures)

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47 pages, 10412 KiB

Open AccessEditor’s ChoiceReview

Magnetic–Plasmonic Core–Shell Nanoparticles: Properties, Synthesis and Applications for Cancer Detection and Treatment

by Alberto Luis Rodriguez-Nieves, Suprava Shah, Mitchell L. Taylor, Madhusudhan Alle and Xiaohua Huang

Nanomaterials 2025, 15(4), 264; https://doi.org/10.3390/nano15040264 - 10 Feb 2025

Viewed by 1474

Abstract

Nanoparticles have been widely used in cancer diagnostics and treatment research due to their unique properties. Magnetic nanoparticles are popular in imaging techniques due to their ability to alter the magnetization field around them. Plasmonic nanoparticles are mainly applied in cancer treatments like [...] Read more.

Nanoparticles have been widely used in cancer diagnostics and treatment research due to their unique properties. Magnetic nanoparticles are popular in imaging techniques due to their ability to alter the magnetization field around them. Plasmonic nanoparticles are mainly applied in cancer treatments like photothermal therapy due to their ability to convert light into heat. While these nanoparticles are popular among their respective fields, magnetic–plasmonic core–shell nanoparticles (MPNPs) have gained popularity in recent years due to the combined magnetic and optical properties from the core and shell. MPNPs have stood out in cancer theranostics as a multimodal platform capable of serving as a contrast agent for imaging, a guidable drug carrier, and causing cellular ablation through photothermal energy conversion. In this review, we summarize the different properties of MPNPs and the most common synthesis approaches. We particularly discuss applications of MPNPs in cancer diagnosis and treatment based on different mechanisms using the magnetic and optical properties of the particles. Lastly, we look into current challenges they face for clinical applications and future perspectives using MPNPs for cancer detection and therapy. Full article

(This article belongs to the Special Issue Extracellular Vesicles: Nanotechnology-Based Isolations, Characterizations, and Applications for Cancer Diagnostics and Monitoring)

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15 pages, 31853 KiB

Open AccessEditor’s ChoiceArticle

The Effect of Carbon Nanofibers on the Microstructure, Chemistry, and Pore Structure of Concrete Made with Fine Recycled Concrete Aggregates

by Nathanial Buettner, Gass Iyacu, Giovanni Dal Poggetto and Ange-Therese Akono

Nanomaterials 2025, 15(4), 253; https://doi.org/10.3390/nano15040253 - 7 Feb 2025

Viewed by 709

Abstract

Recycled aggregate concrete (RAC) is produced using recycled concrete aggregates (RCAs) obtained from crushed old concrete. Although RCAs offer a sustainable alternative to natural aggregates, the poor durability and mechanical performance of RAC limit its widespread application. This study investigated the enhancement of [...] Read more.

Recycled aggregate concrete (RAC) is produced using recycled concrete aggregates (RCAs) obtained from crushed old concrete. Although RCAs offer a sustainable alternative to natural aggregates, the poor durability and mechanical performance of RAC limit its widespread application. This study investigated the enhancement of RAC’s durability and performance through the incorporation of carbon nanofibers (CNFs). A novel processing method was developed to prepare high-slump CNF-modified RAC, and its chemistry, pore structure, and microstructure were analyzed using backscattered scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray powder diffraction (XRD), and mercury intrusion porosimetry (MIP). The results showed that CNFs significantly reduced the porosity and permeability, with a decrease in the porosity by 9.0 wt.% and a decrease in the water permeability by 39.3% at an optimal CNF dosage of 0.5% by weight. Furthermore, CNFs promoted the formation of calcium hydroxide and enhanced the densification of the calcium silicate hydrate (C-S-H) matrix, leading to improved resistance against environmental stressors. These findings provide a critical pathway for designing sustainable, high-durability RAC for structural applications. Full article

(This article belongs to the Section Physical Chemistry at Nanoscale)

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19 pages, 2959 KiB

Open AccessEditor’s ChoiceReview

Nanoimprinted Materials for Nanoparticle Sensing and Removal

by Lavinia Doveri, Azhar Mahmood and Piersandro Pallavicini

Nanomaterials 2025, 15(3), 243; https://doi.org/10.3390/nano15030243 - 5 Feb 2025

Viewed by 572

Abstract

The booming expansion of nanotechnology poses the problem of environmental pollution by nanoparticles (NPs). The available methods for sensing and removing NPs from the environment are typically lengthy and instrumentally demanding. The recent introduction of NP-imprinted polymers (NPIPs), either as films or bulk [...] Read more.

The booming expansion of nanotechnology poses the problem of environmental pollution by nanoparticles (NPs). The available methods for sensing and removing NPs from the environment are typically lengthy and instrumentally demanding. The recent introduction of NP-imprinted polymers (NPIPs), either as films or bulk materials, is an important step toward the simple and fast sensing and removal of NPs from water and air. Similarly to the well-established molecularly imprinted polymers, in NPIPs, an organic or inorganic polymeric material is first obtained with embedded NPs. Then, the NPs are chemically or physically removed by acting as a template, i.e., leaving a polymeric matrix with cavities of the same shape and dimensions. After the first examples were published in 2014, the literature has so far reported an increasing number of NPIPs that are capable of reuptaking NPs from water (or, more rarely, air), with remarkable size and shape selectivity. By laying an NPIP layer on a reporter (typically an electrode), devices are obtained that are capable of sensing NPs. On the other hand, bulk NPIPs can reuptake massive amounts of NPs and have been used for the quantitative removal of NPs from water. This review begins with an overview of NP-imprinted hollow capsules, which can be considered the ancestors of NPIPs, both as conception and as preparative methods. Then, the literature on NPIPs is reviewed. Finally, the possible evolutions of NPIPs are highlighted from the perspective of stepping toward their real-life, field use. Full article

(This article belongs to the Special Issue Advanced Nanomaterials and Nanotechnologies for Micro/Nano-Sensors, 2nd Edition)

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19 pages, 7331 KiB

Open AccessEditor’s ChoiceArticle

Protective Effect of Carbon Dots Derived from Salvia miltiorrhiza Pretreatment in Acute Myocardial Infarction in Rats

by Liyang Dong, Menghan Li, Tianyou Cao, Yafang Zhao, Shuxian Wang, Peng Zou, Yue Zhang, Huihua Qu, Yan Zhao and Hui Kong

Nanomaterials 2025, 15(3), 242; https://doi.org/10.3390/nano15030242 - 5 Feb 2025

Viewed by 688

Abstract

Acute myocardial infarction is an ischemic injury of the myocardium caused by an imbalance in the blood supply to myocardial tissues, which poses a serious threat to human life and health. Oxidative stress has been recognized as a significant contributor to acute myocardial [...] Read more.

Acute myocardial infarction is an ischemic injury of the myocardium caused by an imbalance in the blood supply to myocardial tissues, which poses a serious threat to human life and health. Oxidative stress has been recognized as a significant contributor to acute myocardial infarction. Salvia miltiorrhiza Carbonisata (SMC) is among the most frequently employed herbal remedies for the treatment of acute myocardial infarction; however, the exact identity of its principal active constituents is not well defined. Research indicates that carbon dots (CDs) exhibit significant biological properties. Consequently, we initially synthesized carbon dots (CDs) from Salvia miltiorrhiza Carbonisata, with the objective of exploring how SMC-CDs mitigate isoproterenol (ISO)-induced myocardial infarction (MI) in rats. The results showed that the pretreatment with SMC-CDs markedly enhanced compromised cardiac function, mitigated myocardial fibrosis and the infiltration of inflammatory cells, decreased the size of the infarct, and suppressed cardiomyocyte apoptosis. Furthermore, the antioxidant properties of myocardial tissue were enhanced, and oxidative stress caused by free radicals was effectively mitigated by SMC-CDs, which succeeded in reducing levels of myocardial enzymes and elevating the activity of relevant ATPases. This implies that SMC-CDs could be a potential candidate for novel nanomedicine strategies designed to address cardiovascular ailments. Full article

(This article belongs to the Section Biology and Medicines)

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17 pages, 8357 KiB

Open AccessEditor’s ChoiceArticle

Aluminum–Silica Core–Shell Nanoparticles via Nonthermal Plasma Synthesis

by Thomas Cameron, Bailey Klause, Kristine Q. Loh and Uwe R. Kortshagen

Nanomaterials 2025, 15(3), 237; https://doi.org/10.3390/nano15030237 - 4 Feb 2025

Viewed by 779

Abstract

Aluminum nanoparticles (Al NPs) are interesting for energetic and plasmonic applications due to their enhanced size-dependent properties. Passivating the surface of these particles is necessary to avoid forming a native oxide layer, which can degrade energetic and optical characteristics. This work utilized a [...] Read more.

Aluminum nanoparticles (Al NPs) are interesting for energetic and plasmonic applications due to their enhanced size-dependent properties. Passivating the surface of these particles is necessary to avoid forming a native oxide layer, which can degrade energetic and optical characteristics. This work utilized a radiofrequency (RF)-driven capacitively coupled argon/hydrogen plasma to form surface-modified Al NPs from aluminum trichloride (AlCl₃) vapor and 5% silane in argon (dilute SiH₄). Varying the power and dilute SiH₄ flow rate in the afterglow of the plasma led to the formation of varying nanoparticle morphologies: Al–SiO₂ core–shell, Si–Al₂O₃ core–shell, and Al–Si Janus particles. Scanning transmission electron microscopy with a high-angle annular dark-field detector (STEM-HAADF) and energy-dispersive X-ray spectroscopy (EDS) were employed for characterization. The surfaces of the nanoparticles and sample composition were characterized and found to be sensitive to changes in RF power input and dilute SiH₄ flow rate. This work demonstrates a tunable range of Al–SiO₂ core–shell nanoparticles where the Al-to-Si ratio could be varied by changing the plasma parameters. Thermal analysis measurements performed on plasma-synthesized Al, crystalline Si, and Al–SiO₂ samples are compared to those from a commercially available 80 nm Al nanopowder. Core–shell particles exhibit an increase in oxidation temperature from 535 °C for Al to 585 °C for Al–SiO₂. This all-gas-phase synthesis approach offers a simple preparation method to produce high-purity heterostructured Al NPs. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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21 pages, 4668 KiB

Open AccessEditor’s ChoiceArticle

Growth of ZnO Nanoparticles Using Microwave Hydrothermal Method—Search for Defect-Free Particles

by Julita Rosowska, Jarosław Kaszewski, Marcin Krajewski, Artur Małolepszy, Bartłomiej S. Witkowski, Łukasz Wachnicki, Lev-Ivan Bulyk, Piotr Sybilski, Marek Godlewski and Michał M. Godlewski

Nanomaterials 2025, 15(3), 230; https://doi.org/10.3390/nano15030230 - 31 Jan 2025

Viewed by 931

Abstract

This study investigated the influence of chemical reagent selection on the properties of ZnO nanoparticles synthesized using the microwave-assisted hydrothermal method to control the intensities of near-band-edge (NBE) and defect-related deep-level (DLE) emissions. Two zinc precursors—zinc nitrate and zinc chloride—along with three different [...] Read more.

This study investigated the influence of chemical reagent selection on the properties of ZnO nanoparticles synthesized using the microwave-assisted hydrothermal method to control the intensities of near-band-edge (NBE) and defect-related deep-level (DLE) emissions. Two zinc precursors—zinc nitrate and zinc chloride—along with three different precipitating agents (NaOH, KOH, and NH₄OH) were used. ZnO nanoparticles from the ZnCl₂ precursor exhibited two orders of magnitude higher NBE/DLE intensity ratio compared to those obtained from zinc nitrate characterized by a higher contribution from defect-related emissions. Chlorine ions in ZnO nanoparticles play a key role in passivating defects by forming V₀-Cl₂ complexes, quenching luminescence associated with oxygen vacancies (V₀). Thermal treatment in a nitrogen atmosphere enhanced defect-related luminescence, possibly due to chlorine atom diffusion. This study highlights a successful synthesis of ZnO nanoparticles with low defect-related luminescence (DLE) achieved via the microwave-assisted hydrothermal method, a result rarely reported in the literature. The results emphasize the importance of reagent selection in controlling the morphology and optical properties, especially the defect density of ZnO nanoparticles. Optimizing these properties is crucial for biomedical applications such as bioimaging, antibacterial treatments, and photocatalysis. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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14 pages, 23596 KiB

Open AccessEditor’s ChoiceArticle

Evaluating the In Situ Effects of Whole Protein Coronas on the Biosensing of Antibody-Immobilized Nanoparticles Using Two-Color Fluorescence Nanoparticle Tracking Analysis

by Heeju Joung, Gwi Ju Jang, Ji Yeon Jeong, Goeun Lim and Sang Yun Han

Nanomaterials 2025, 15(3), 220; https://doi.org/10.3390/nano15030220 - 30 Jan 2025

Viewed by 776

Abstract

The formation of protein coronas around engineered nanoparticles (ENPs) in biological environments is critical in nanomedicine, as these coronas significantly influence the biological behavior of ENPs. Despite extensive research on protein coronas, understanding the in situ influence of whole (soft plus hard) protein [...] Read more.

The formation of protein coronas around engineered nanoparticles (ENPs) in biological environments is critical in nanomedicine, as these coronas significantly influence the biological behavior of ENPs. Despite extensive research on protein coronas, understanding the in situ influence of whole (soft plus hard) protein coronas has remained challenging. In this study, we demonstrate a strategy to assess the in situ effects of whole coronas on the model biosensing of anti-IgG using IgG-conjugated gold nanoparticles (IgG-AuNPs) through fluorescence nanoparticle tracking analysis (F-NTA), which enables the selective tracking of fluorescent particles within complex media. In our approach, anti-IgG and IgG-AuNPs were labeled with distinct fluorescent dyes. The accordance in hydrodynamic diameter distributions observed at two different wavelengths verifies the successful capture of anti-IgG on the IgG-AuNPs. The counting of fluorescent anti-IgG within the size distribution allows for a quantitative assessment of biosensing efficiency. This method was applied to evaluate the effects of four protein coronas—human serum albumin, high-density lipoproteins, immunoglobulin G, and fibrinogen—as well as their mixture across varying incubation times and concentrations. The results suggest that the physical presence of whole protein coronas surrounding the IgG-AuNPs may assist the biosensing interaction in situ rather than screening it. Full article

(This article belongs to the Special Issue Advanced Studies in Bionanomaterials)

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34 pages, 11344 KiB

Open AccessEditor’s ChoiceArticle

New Nanobioceramics Based on Hydroxyapatite for Biomedical Applications: Stability and Properties

by Carmen Steluta Ciobanu, Daniela Predoi, Simona Liliana Iconaru, Catalin Constantin Negrila, Damien Leduc, Liliana Ghegoiu, Coralia Bleotu, Mounsif Ech Cherif El Kettani, Roxana Trusca, Philippe Zelmar and Mihai Valentin Predoi

Nanomaterials 2025, 15(3), 224; https://doi.org/10.3390/nano15030224 - 30 Jan 2025

Viewed by 1041

Abstract

In this work, we report for the first time the development and complex characterization of new bioceramics based on hydroxyapatite (HAp, Ca₁₀(PO₄)₆(OH)₂). On the other hand, the lyophilization process was used for the first time [...] Read more.

In this work, we report for the first time the development and complex characterization of new bioceramics based on hydroxyapatite (HAp, Ca₁₀(PO₄)₆(OH)₂). On the other hand, the lyophilization process was used for the first time in this research. The samples were obtained by a modified coprecipitation method and were dried by lyophilization (lyophilized hydroxyapatite (HApLF) and lyophilized zinc-doped hydroxyapatite (5ZnHApLF)). Valuable information about the HApLF and 5ZnHApLF stability was obtained through nondestructive ultrasound measurements. The X-ray diffraction (XRD) studies revealed the phase and the effects of the incorporation of Zn ions into the HAp structure. The chemical composition of the samples was evaluated by energy dispersive X-ray analysis (EDS) and X-ray photoelectron spectroscopy (XPS). Information about the functional groups present in the HApLF and 5ZnHApLF was obtained using Fourier Transform Infrared Spectroscopy (FTIR) studies. The morphology of HApLF and 5ZnHApLF pellets was observed by scanning electron microscopy (SEM). The surface topography of HApLF and 5ZnHApLF pellets was studied with the aid of atomic force microscopy (AFM). Details regarding the roughness of the samples were also obtained using AFM topographies and SEM images. A complementary study was also carried out on a larger analysis surface using a Scanning Acoustic Microscope (SAM). The SAM was used for the first time to analyze the surface of HAp and 5ZnHAp pellets. The biological properties of the HApLF and 5ZnHApLF pellets was investigated with the aid of MG63 and human gingival fibroblasts (HGF-1) cell lines. The results of the cell viability assay highlighted that both the HApLF and 5ZnHApLF pellets exhibited good biological activity. Moreover, SEM and AFM studies were conducted in order to emphasize the development of MG63 and HGF-1 cells on the pellet’s surface. Both SEM and AFM images depicted that the pellets’ surface favored the cell attachment and development of MG63 and HGF-1 cells. Furthermore, the antimicrobial properties of the HApLF and 5ZnHApLF were evaluated against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, and Candida albicans ATCC 10231. The results of the antimicrobial assays highlighted that the 5ZnHApLF exhibited a strong antimicrobial activity against the tested microbial strains. The results of the biological assays suggested that the samples show great potential for being used in the development of novel materials for biomedical applications. Full article

(This article belongs to the Special Issue The Synthesis of Antibacterial Nanomaterials and Their Biomedical Applications)

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33 pages, 5990 KiB

Open AccessEditor’s ChoiceReview

Comparison of Single Atoms vs. Sub-Nanoclusters as Co-Catalysts in Perovskites and Metal Oxides for Photocatalytic Technologies

by Anastasia V. Spyrou, Konstantinos Zodhiates and Yiannis Deligiannakis

Nanomaterials 2025, 15(3), 226; https://doi.org/10.3390/nano15030226 - 30 Jan 2025

Viewed by 1584

Abstract

Adatoms as co-catalysts may play a key role in photocatalysis, yet control of their exact configuration remains challenging. Specifically, there is converging evidence that ultra-small structures may be optimal as co-catalysts; however, a comprehensive distinction between single atoms (SAs), sub-nanoclusters (SNCs), and quantum-sized [...] Read more.

Adatoms as co-catalysts may play a key role in photocatalysis, yet control of their exact configuration remains challenging. Specifically, there is converging evidence that ultra-small structures may be optimal as co-catalysts; however, a comprehensive distinction between single atoms (SAs), sub-nanoclusters (SNCs), and quantum-sized small particles (QSSPs) has yet to be established. Herein, we present a critical review addressing these distinctions, along with challenges related to the controlled synthesis of SAs, SNCs, and QSSPs; their detection methods; and their functional benefits in photocatalysis. Our discussion focuses on perovskite oxides (e.g., such as ABO₃, where A and B are cations) and metal oxides (M_xO_y, where M is a metal) decorated with adatoms, which demonstrate superior photocatalytic performance compared to their unmodified counterparts. Finally, we highlight cases of misinterpretation between SA, SNC, and QSSP configurations emerging from limitations in high-resolution detection techniques and synthesis methods. Full article

(This article belongs to the Section Energy and Catalysis)

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12 pages, 7565 KiB

Open AccessEditor’s ChoiceArticle

Deterministic Fabrication of Fluorescent Nanostructures Featuring Distinct Optical Transitions

by Marijn Rikers, Ayesheh Bashiri, Ángela Barreda, Michael Steinert, Duk-Yong Choi, Thomas Pertsch and Isabelle Staude

Nanomaterials 2025, 15(3), 219; https://doi.org/10.3390/nano15030219 - 29 Jan 2025

Viewed by 653

Abstract

The precise and deterministic integration of fluorescent emitters with photonic nanostructures is an important challenge in nanophotonics and key to the realization of hybrid photonic systems, supporting effects such as emission enhancement, directional emission, and strong coupling. Such integration typically requires the definition [...] Read more.

The precise and deterministic integration of fluorescent emitters with photonic nanostructures is an important challenge in nanophotonics and key to the realization of hybrid photonic systems, supporting effects such as emission enhancement, directional emission, and strong coupling. Such integration typically requires the definition or immobilization of the emitters at defined positions with nanoscale precision. While various methods were already developed for creating localized emitters, in this work we present a new method for the deterministic fabrication of fluorescent nanostructures featuring well-defined optical transitions; it works with a minimal amount of steps and is scalable. Specifically, electron-beam lithography is used to directly pattern a mixture of the negative-tone electron-beam resist with the europium complex Eu(TTA)₃, which exhibits both electric and magnetic dipolar transitions. Crucially, the lithography process enables precise control over the shape and position of the resulting fluorescent structures with a feature size of approx. 100

n

m

. We demonstrate that the Eu(TTA)₃ remains fluorescent after exposure, confirming that the electron beam does not alter the structure the optical transitions. This work supports the experimental study of local density of optical states in nanophotonics. It also expands the knowledge base of fluorescent polymer materials, which can have applications in polymer-based photonic devices. Altogether, the presented fabrication method opens the door for the realization of hybrid nanophotonic systems incorporating fluorescent emitters for light-emitting dielectric metasurfaces. Full article

(This article belongs to the Section Nanofabrication and Nanomanufacturing)

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25 pages, 6681 KiB

Open AccessEditor’s ChoiceReview

Gamma Radiation in the Synthesis of Inorganic Silica-Based Nanomaterials: A Review

by Andreea Simona Baltac and Raul-Augustin Mitran

Nanomaterials 2025, 15(3), 218; https://doi.org/10.3390/nano15030218 - 29 Jan 2025

Viewed by 917

Abstract

Gamma radiation offers a versatile approach for the synthesis of silica-based nanomaterials, leveraging high-energy radiolysis to produce pure and finely structured composites without the need for surfactants or capping agents. This review explores the underlying mechanisms of γ-ray-induced radiolytic reduction, detailing the interaction [...] Read more.

Gamma radiation offers a versatile approach for the synthesis of silica-based nanomaterials, leveraging high-energy radiolysis to produce pure and finely structured composites without the need for surfactants or capping agents. This review explores the underlying mechanisms of γ-ray-induced radiolytic reduction, detailing the interaction of radiolytic species with silica matrices to synthesize metallic and hybrid nanomaterials. Emphasis is placed on the synthesis of silver and noble metal composites, which demonstrate promising properties for catalytic, antimicrobial, and sensing applications. The influence of synthesis parameters, such as dose, pH, and matrix characteristics, on nanoparticle size and yield is discussed. Emerging applications of these materials in biomedical devices and environmental technologies are presented. While γ-ray synthesis circumvents issues of contamination and scalability inherent in chemical methods, challenges such as accessibility to radiation sources and control over nanoparticle morphology remain. Future research directions are proposed, including the extension of this technique to multimetallic systems, sulfide-based nanocomposites, and hybrid materials. Full article

(This article belongs to the Special Issue Recent Advancements in Mesoporous Nanomaterials: Synthesis, Characterization and Catalytic Applications (2nd Edition))

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31 pages, 5103 KiB

Open AccessEditor’s ChoiceReview

Boron Nitride-Supported Metal Catalysts for the Synthesis and Decomposition of Ammonia and Formic Acid

by Marta Yruela-Garrido, Eduardo Campos-Castellanos, María V. Morales, Inmaculada Rodríguez-Ramos and Antonio Guerrero-Ruiz

Nanomaterials 2025, 15(3), 212; https://doi.org/10.3390/nano15030212 - 28 Jan 2025

Cited by 1 | Viewed by 1013

Abstract

This review explores the recent advancements in the application of boron nitride (BN) as a support material for metallic nanoparticles, highlighting its potential in fostering sustainable chemical reactions when employed as a heterogeneous catalyst. Two key processes, both critical to hydrogen storage and [...] Read more.

This review explores the recent advancements in the application of boron nitride (BN) as a support material for metallic nanoparticles, highlighting its potential in fostering sustainable chemical reactions when employed as a heterogeneous catalyst. Two key processes, both critical to hydrogen storage and transport, are examined in detail. First, the reversible synthesis and decomposition of ammonia using BN-supported metallic catalysts has emerged as a promising technology. This approach facilitates the preparation of Ru nanoparticles with precisely structured surface atomic ensembles, such as B5 sites, which are critical for maximizing catalytic efficiency. Second, the review emphasizes the role of BN-supported catalysts in the production of formic acid (FA), a process intrinsically linked to the reuse of carbon dioxide. In this context, hydrogen and carbon dioxide—potentially sourced from atmospheric capture—serve as reactants. BN’s high CO₂ adsorption capacity makes it an ideal support material for such applications. Moreover, FA can serve as a source of hydrogen through decomposition or as a precursor to alternative chemicals like carbon monoxide (CO) via dehydration, further underscoring its versatility in sustainable catalysis. Full article

(This article belongs to the Section Energy and Catalysis)

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42 pages, 7520 KiB

Open AccessEditor’s ChoiceReview

Applications of MOF-Based Nanocomposites in Heat Exchangers: Innovations, Challenges, and Future Directions

by Talha Bin Nadeem, Muhammad Imran and Emad Tandis

Nanomaterials 2025, 15(3), 205; https://doi.org/10.3390/nano15030205 - 27 Jan 2025

Cited by 1 | Viewed by 1136

Abstract

Metal–organic frameworks (MOFs) have garnered significant attention in recent years for their potential to revolutionize heat exchanger performance, thanks to their high surface area, tunable porosity, and exceptional adsorption capabilities. This review focuses on the integration of MOFs into heat exchangers to enhance [...] Read more.

Metal–organic frameworks (MOFs) have garnered significant attention in recent years for their potential to revolutionize heat exchanger performance, thanks to their high surface area, tunable porosity, and exceptional adsorption capabilities. This review focuses on the integration of MOFs into heat exchangers to enhance heat transfer efficiency, improve moisture management, and reduce energy consumption in Heating, Ventilation and Air Conditioning (HVAC) and related systems. Recent studies demonstrate that MOF-based coatings can outperform traditional materials like silica gel, achieving superior water adsorption and desorption rates, which is crucial for applications in air conditioning and dehumidification. Innovations in synthesis techniques, such as microwave-assisted and surface functionalization methods, have enabled more cost-effective and scalable production of MOFs, while also enhancing their thermal stability and mechanical strength. However, challenges related to the high costs of MOF synthesis, stability under industrial conditions, and large-scale integration remain significant barriers. Future developments in hybrid nanocomposites and collaborative efforts between academia and industry will be key to advancing the practical adoption of MOFs in heat exchanger technologies. This review aims to provide a comprehensive understanding of current advancements, challenges, and opportunities, with the goal of guiding future research toward more sustainable and efficient thermal management solutions. Full article

(This article belongs to the Special Issue Metal Organic Framework (MOF)-Based Micro/Nanoscale Materials)

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51 pages, 69281 KiB

Open AccessEditor’s ChoiceReview

Two-Dimensional Nanostructured Ti₃C₂T_x MXene for Ceramic Materials: Preparation and Applications

by Xiao-Tong Jia, Hong-Wei Xing, Xing-Wang Cheng, Zhao-Hui Zhang, Qiang Wang, Jin-Zhao Zhou, Yang-Yu He and Wen-Jun Li

Nanomaterials 2025, 15(3), 204; https://doi.org/10.3390/nano15030204 - 27 Jan 2025

Viewed by 895

Abstract

Ti₃C₂T_x MXene, a novel two-dimensional transition metal carbide with nanoscale dimensions, has attracted significant attention due to its exceptional structural and performance characteristics. This review comprehensively examines various preparation methods for Ti₃C₂T_x MXene, [...] Read more.

Ti₃C₂T_x MXene, a novel two-dimensional transition metal carbide with nanoscale dimensions, has attracted significant attention due to its exceptional structural and performance characteristics. This review comprehensively examines various preparation methods for Ti₃C₂T_x MXene, including acid etching, acid–salt composite etching, alkali etching, and molten salt etching. It further discusses several strategies for interlayer exfoliation, highlighting the advantages and limitations of each method. The effects of these techniques on the nanostructure, surface functional groups, interlayer spacing, and overall performance of Ti₃C₂T_x MXene are evaluated. Additionally, this paper explores the diverse applications of Ti₃C₂T_x MXene in ceramic materials, particularly its role in enhancing mechanical properties, electrical and thermal conductivity, as well as oxidation and corrosion resistance. The primary objective of the review is to provide scientific insights and theoretical guidance for the preparation of Ti₃C₂T_x MXene and its further research and innovative applications in ceramic materials, advancing the development of high-performance, multifunctional ceramics. Full article

(This article belongs to the Special Issue Ceramic Matrix Nanocomposites)

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21 pages, 10584 KiB

Open AccessEditor’s ChoiceReview

Principles and Applications of Two-Dimensional Semiconductor Material Devices for Reconfigurable Electronics

by Jiong Pan, Yike Zhang, Jiaju Yin, Pengwen Guo, Yi Yang and Tian-Ling Ren

Nanomaterials 2025, 15(3), 201; https://doi.org/10.3390/nano15030201 - 27 Jan 2025

Viewed by 1034

Abstract

With the advances in edge computing and artificial intelligence, the demands of multifunctional electronics with large area efficiency are increased. As the scaling down of the conventional transistor is restricted by physical limits, reconfigurable electronics are developed to promote the functional integration of [...] Read more.

With the advances in edge computing and artificial intelligence, the demands of multifunctional electronics with large area efficiency are increased. As the scaling down of the conventional transistor is restricted by physical limits, reconfigurable electronics are developed to promote the functional integration of integrated circuits. Reconfigurable electronics refer to electronics with switchable functionalities, including reconfigurable logic operation functionalities and reconfigurable responses to electrical or optical signals. Reconfigurable electronics integrate data-processing capabilities with reduced size. Two-dimensional (2D) semiconductor materials exhibit excellent modulation capabilities through electrical and optical signals, and structural designs of 2D material devices achieve versatile and switchable functionalities. 2D semiconductors have great potential to develop advanced reconfigurable electronics. Recent years witnessed the rapid development of 2D material devices for reconfigurable electronics. This work focuses on the working principles of 2D material devices used for reconfigurable electronics, discusses applications of 2D-material-based reconfigurable electronics in logic operation and artificial intelligence, and further provides a future outlook for the development of reconfigurable electronics based on 2D material devices. Full article

(This article belongs to the Special Issue Advanced 2D Materials for Emerging Application)

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19 pages, 3162 KiB

Open AccessEditor’s ChoiceArticle

A Multi-Method Approach to Analyzing MOFs for Chemical Warfare Simulant Capture: Molecular Simulation, Machine Learning, and Molecular Fingerprints

by Zhongyuan Ming, Min Zhang, Shouxin Zhang, Xiaopeng Li, Xiaoshan Yan, Kexin Guan, Yu Li, Yufeng Peng, Jinfeng Li, Heguo Li, Yue Zhao and Zhiwei Qiao

Nanomaterials 2025, 15(3), 183; https://doi.org/10.3390/nano15030183 - 24 Jan 2025

Viewed by 933

Abstract

Mustard gas (HD) is a well-known chemical warfare agent, recognized for its extreme toxicity and severe hazards. Metal–organic frameworks (MOFs), with their unique structural properties, show significant potential for HD adsorption applications. Due to the extreme hazards of HD, most experimental studies focus [...] Read more.

Mustard gas (HD) is a well-known chemical warfare agent, recognized for its extreme toxicity and severe hazards. Metal–organic frameworks (MOFs), with their unique structural properties, show significant potential for HD adsorption applications. Due to the extreme hazards of HD, most experimental studies focus on its simulants, but molecular simulation research on these simulants remains limited. Simulation analyses of simulants can uncover structure–performance relationships and enable experimental validation, optimizing methods, and improving material design and performance predictions. This study integrates molecular simulations, machine learning (ML), and molecular fingerprinting (MFs) to identify MOFs with high adsorption performance for the HD simulant diethyl sulfide (DES), followed by in-depth structural analysis and comparison. First, MOFs are categorized into Top, Middle, and Bottom materials based on their adsorption efficiency. Univariate analysis, machine learning, and molecular fingerprinting are then used to identify and compare the distinguishing features and fingerprints of each category. Univariate analysis helps identify the optimal structural ranges of Top and Bottom materials, providing a reference for initial material screening. Machine learning feature importance analysis, combined with SHAP methods, identifies the key features that most significantly influence model predictions across categories, offering valuable insights for future material design. Molecular fingerprint analysis reveals critical fingerprint combinations, showing that adsorption performance is optimized when features such as metal oxides, nitrogen-containing heterocycles, six-membered rings, and C=C double bonds co-exist. The integrated analysis using HTCS, ML, and MFs provides new perspectives for designing high-performance MOFs and demonstrates significant potential for developing materials for the adsorption of CWAs and their simulants. Full article

(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)

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25 pages, 2595 KiB

Open AccessEditor’s ChoiceReview

The Role of Nanoparticles in Wine Science: Innovations and Applications

by Agnieszka Mierczynska-Vasilev

Nanomaterials 2025, 15(3), 175; https://doi.org/10.3390/nano15030175 - 23 Jan 2025

Viewed by 965

Abstract

Viticulture, the science of growing, cultivating, and harvesting grapes, and enology, the art and science of making wine, are rapidly evolving through innovative approaches aimed at improving the quality and efficiency of grape and wine production. This review explores the emerging use of [...] Read more.

Viticulture, the science of growing, cultivating, and harvesting grapes, and enology, the art and science of making wine, are rapidly evolving through innovative approaches aimed at improving the quality and efficiency of grape and wine production. This review explores the emerging use of nanoparticles, in particular gold, silver, and magnetic nanoparticles, to improve the quality, safety, and sustainability of both grape growing and winemaking processes. The unique properties of these nanoparticles, such as their small size, high surface area, and distinct chemical properties, enable them to address key challenges within the industry. In viticulture, nanoparticles have shown potential in protecting vines from pathogens, optimizing grape yield, and improving quality. In enology, nanoparticles are making a significant contribution to microbial control, reducing spoilage and refining wine analysis techniques, leading to improved product quality and safety. This review also highlights the synergy between different types of nanoparticles and their diverse applications, from microbial control in wine production to their use in innovative packaging solutions. In addition, nanoparticles have the potential to reduce dependence on agrochemicals and improve the sustainability of wine production, which is a promising avenue for future research. However, the integration of nanoparticles in viticulture and enology also poses regulatory and safety challenges, including the potential for nanoparticles to leach into wine products. Further research and regulatory advances are essential to ensure the safe and effective use of these technologies in winemaking. Overall, nanoparticles offer significant benefits to the wine industry, driving improvements in efficiency, sustainability, and quality. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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11 pages, 4983 KiB

Open AccessEditor’s ChoiceArticle

Thin Hydrogenated Amorphous Silicon Carbide Layers with Embedded Ge Nanocrystals

by Zdeněk Remeš, Jiří Stuchlík, Jaroslav Kupčík and Oleg Babčenko

Nanomaterials 2025, 15(3), 176; https://doi.org/10.3390/nano15030176 - 23 Jan 2025

Viewed by 739

Abstract

The in situ combination of plasma-enhanced chemical vapor deposition (PECVD) and vacuum evaporation in the same vacuum chamber allowed us to integrate germanium nanocrystals (Ge NCs) into hydrogenated amorphous silicon carbide (a-SiC:H) thin films deposited from monomethyl silane diluted with hydrogen. Transmission electron [...] Read more.

The in situ combination of plasma-enhanced chemical vapor deposition (PECVD) and vacuum evaporation in the same vacuum chamber allowed us to integrate germanium nanocrystals (Ge NCs) into hydrogenated amorphous silicon carbide (a-SiC:H) thin films deposited from monomethyl silane diluted with hydrogen. Transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) spectroscopy were used for the microscopic characterization, while photothermal deflection spectroscopy (PDS) and near-infrared photoluminescence spectroscopy (NIR PL) were for optical characterization. The presence of Ge NCs embedded in the amorphous a-Si:C:H thin films was confirmed by TEM and EDX. The embedded Ge NCs increased optical absorption in the NIR spectral region. The quenching of a-SiC:H NIR PL due to the presence of Ge indicates that the diffusion length of free charge carriers in a-SiC:H is in the range of a few tens of nm, an order of magnitude less than in a-Si:H. The optical properties of a-SiC:H films were degraded after vacuum annealing at 550 °C. Full article

(This article belongs to the Section Nanocomposite Materials)

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15 pages, 3951 KiB

Open AccessEditor’s ChoiceArticle

Mild Temperature Thermal Treatments of Gold-Exfoliated Monolayer MoS₂

by Emanuele Sangiorgi, Antonino Madonia, Gianmarco Laurella, Salvatore Ethan Panasci, Emanuela Schilirò, Filippo Giannazzo, Igor Píš, Federica Bondino, György Zoltán Radnóczi, Viktória Kovács-Kis, Béla Pécz, Gianpiero Buscarino, Franco Mario Gelardi, Marco Cannas and Simonpietro Agnello

Nanomaterials 2025, 15(3), 160; https://doi.org/10.3390/nano15030160 - 22 Jan 2025

Viewed by 909

Abstract

Monolayer molybdenum disulfide is considered an extremely promising two-dimensional material for innovative electronics due to its direct bandgap and high charge-carrier mobility. The optical and electronic properties of monolayer MoS₂ can, however, be strongly influenced by the specific synthesis route, posing challenges [...] Read more.

Monolayer molybdenum disulfide is considered an extremely promising two-dimensional material for innovative electronics due to its direct bandgap and high charge-carrier mobility. The optical and electronic properties of monolayer MoS₂ can, however, be strongly influenced by the specific synthesis route, posing challenges for industrial-scale production. In this study, we investigated the effects of moderate temperature thermal treatments under a controlled O₂ atmosphere on the properties of monolayer MoS₂ flakes. We found that the treatments can effectively tune the doping level of monolayer MoS₂. Notably, 225 °C was identified as the optimal temperature for enhancing its optical emission properties. Our findings suggest that the removal of sulfur vacancies and impurities underlies these effects, demonstrating a promising approach for tuning the properties of monolayer MoS₂ at mild temperatures. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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53 pages, 9820 KiB

Open AccessEditor’s ChoiceReview

Surface Functionalization of Nanocarriers with Anti-EGFR Ligands for Cancer Active Targeting

by Alessandra Spada and Sandrine Gerber-Lemaire

Nanomaterials 2025, 15(3), 158; https://doi.org/10.3390/nano15030158 - 21 Jan 2025

Viewed by 1635

Abstract

Active cancer targeting consists of the selective recognition of overexpressed biomarkers on cancer cell surfaces or within the tumor microenvironment, enabled by ligands conjugated to drug carriers. Nanoparticle (NP)-based systems are highly relevant for such an approach due to their large surface area [...] Read more.

Active cancer targeting consists of the selective recognition of overexpressed biomarkers on cancer cell surfaces or within the tumor microenvironment, enabled by ligands conjugated to drug carriers. Nanoparticle (NP)-based systems are highly relevant for such an approach due to their large surface area which is amenable to a variety of chemical modifications. Over the past decades, several studies have debated the efficiency of passive targeting, highlighting active targeting as a more specific and selective approach. The choice of conjugation chemistry for attaching ligands to nanocarriers is critical to ensure a stable and robust system. Among the panel of cancer biomarkers, the epidermal growth factor receptor (EGFR) stands as one of the most frequently overexpressed receptors in different cancer types. The design and development of nanocarriers with surface-bound anti-EGFR ligands are vital for targeted therapy, relying on their facilitated capture by EGFR-overexpressing tumor cells and enabling receptor-mediated endocytosis to improve drug accumulation within the tumor microenvironment. In this review, we examine several examples of the most recent and significant anti-EGFR nanocarriers and explore the various conjugation strategies for NP functionalization with anti-EGFR biomolecules and small molecular ligands. In addition, we also describe some of the most common characterization techniques to confirm and analyze the conjugation patterns. Full article

(This article belongs to the Special Issue The Future of Nanotechnology: Healthcare and Manufacturing)

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23 pages, 5469 KiB

Open AccessEditor’s ChoiceArticle

Shutter-Synchronized Molecular Beam Epitaxy for Wafer-Scale Homogeneous GaAs and Telecom Wavelength Quantum Emitter Growth

by Elias Kersting, Hans-Georg Babin, Nikolai Spitzer, Jun-Yong Yan, Feng Liu, Andreas D. Wieck and Arne Ludwig

Nanomaterials 2025, 15(3), 157; https://doi.org/10.3390/nano15030157 - 21 Jan 2025

Viewed by 1337

Abstract

Quantum dot (QD)-based single-photon emitter devices today are based on self-assembled random position nucleated QDs emitting at random wavelengths. Deterministic QD growth in position and emitter wavelength would be highly appreciated for industry-scale high-yield device manufacturing from wafers. Local droplet etching during molecular [...] Read more.

Quantum dot (QD)-based single-photon emitter devices today are based on self-assembled random position nucleated QDs emitting at random wavelengths. Deterministic QD growth in position and emitter wavelength would be highly appreciated for industry-scale high-yield device manufacturing from wafers. Local droplet etching during molecular beam epitaxy is an all in situ method that allows excellent density control and predetermines the nucleation site of quantum dots. This method can produce strain-free GaAs QDs with excellent photonic and spin properties. Here, we focus on the emitter wavelength homogeneity. By wafer rotation-synchronized shutter opening time and adapted growth parameters, we grow QDs with a narrow peak emission wavelength homogeneity with no more than 1.2 nm shifts on a 45 mm diameter area and a narrow inhomogeneous ensemble broadening of only 2 nm at 4 K. The emission wavelength of these strain-free GaAs QDs is <800 nm, attractive for quantum optics experiments and quantum memory applications. We can use a similar random local droplet nucleation, nanohole drilling, and now, InAs infilling to produce QDs emitting in the telecommunication optical fiber transparency window around 1.3 µm, the so-called O-band. For this approach, we demonstrate good wavelength homogeneity and excellent density homogeneity beyond the possibilities of standard Stranski–Krastanov self-assembly. We discuss our methodology, structural and optical properties, and limitations set by our current setup capabilities. Full article

(This article belongs to the Section Nanophotonics Materials and Devices)

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16 pages, 6768 KiB

Open AccessEditor’s ChoiceArticle

Mid-Infrared High-Power InGaAsSb/AlGaInAsSb Multiple-Quantum-Well Laser Diodes Around 2.9 μm

by Hongguang Yu, Chengao Yang, Yihang Chen, Jianmei Shi, Juntian Cao, Zhengqi Geng, Zhiyuan Wang, Haoran Wen, Enquan Zhang, Yu Zhang, Hao Tan, Donghai Wu, Yingqiang Xu, Haiqiao Ni and Zhichuan Niu

Nanomaterials 2025, 15(2), 139; https://doi.org/10.3390/nano15020139 - 17 Jan 2025

Viewed by 724

Abstract

Antimonide laser diodes, with their high performance above room temperature, exhibit significant potential for widespread applications in the mid-infrared spectral region. However, the laser’s performance significantly degrades as the emission wavelength increases, primarily due to severe quantum-well hole leakage and significant non-radiative recombination. [...] Read more.

Antimonide laser diodes, with their high performance above room temperature, exhibit significant potential for widespread applications in the mid-infrared spectral region. However, the laser’s performance significantly degrades as the emission wavelength increases, primarily due to severe quantum-well hole leakage and significant non-radiative recombination. In this paper, we put up an active region with a high valence band offset and excellent crystalline quality with high luminescence to improve the laser’s performance. The miscibility gap of the InGaAsSb alloy was systematically investigated by calculating the critical temperatures based on the delta lattice parameter model. As the calculation results show, In_0.54Ga_0.46As_0.23Sb_0.77, with a compressive strain of 1.74%, used as the quantum well, is out of the miscibility gap with no spinodal decomposition. The quantum wells exhibit high crystalline quality, as evidenced by distinct satellite peaks in XRD curves with a full width at half maximum (FWHM) of 56 arcseconds for the zeroth-order peak, a smooth surface with a root mean square (RMS) roughness of 0.19 nm, room-temperature photoluminescence with high luminous efficiency and narrow FHWM of 35 meV, and well-defined interfaces. These attributes effectively suppress non-radiative recombination, thereby enhancing internal quantum efficiency in the antimonide laser. Furthermore, a novel epitaxial laser structure was designed to acquire low optical absorption loss by decreasing the optical confinement factor in the cladding layer and implementing gradient doping in the p-type cladding layer. The continuous-wave output power of 310 mW was obtained at an injection current of 4.6 A and a heatsink temperature of 15 °C from a 1500 × 100 μm² single emitter. The external quantum efficiency of 53% was calculated with a slope efficiency of 0.226 W/A considering both of the uncoated facets. More importantly, the lasing wavelength of our laser exhibited a significant blue shift from 3.4 μm to 2.9 μm, which agrees with our calculated results when modeling the interdiffusion process in a quantum well. Therefore, the interdiffusion process must be considered for proper design and epitaxy to achieve mid-infrared high-power and high-efficiency antimonide laser diodes. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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23 pages, 7326 KiB

Open AccessEditor’s ChoiceArticle

Significance of Tool Coating Properties and Compacted Graphite Iron Microstructure for Tool Selection in Extreme Machining

by Anna Maria Esposito, Qianxi He, Jose M. DePaiva and Stephen C. Veldhuis

Nanomaterials 2025, 15(2), 130; https://doi.org/10.3390/nano15020130 - 16 Jan 2025

Viewed by 841

Abstract

This study aims to determine the extent to which coating composition and workpiece properties impact machinability and tool selection when turning Compacted Graphite Iron (CGI) under extreme roughing conditions. Two CGI workpieces, differing in pearlite content and graphite nodularity, were machined at a [...] Read more.

This study aims to determine the extent to which coating composition and workpiece properties impact machinability and tool selection when turning Compacted Graphite Iron (CGI) under extreme roughing conditions. Two CGI workpieces, differing in pearlite content and graphite nodularity, were machined at a cutting speed of 180 m/min, feed rate of 0.18 mm/rev, and depth of cut of 3 mm. To assess the impact of tool properties across a wide range of commercially available tools, four diverse multilayered cemented carbide tools were evaluated: Tool A and Tool B with a thin AlTiSiN PVD coating, Tool C with a thick Al₂O₃-TiCN CVD coating, and Tool D with a thin Al₂O₃-TiC PVD coating. The machinability of CGI and wear mechanisms were analyzed using pre-cutting characterization, in-process optical microscopy, and post-test SEM analysis. The results revealed that CGI microstructural variations only affected tool life for Tool A, with a 110% increase in tool life between machining CGI Grade B and Grade A, but that the effects were negligible for all other tools. Tool C had a 250% and 70% longer tool life compared to the next best performance (Tool A) for CGI Grade A and CGI Grade B, respectively. With its thick CVD-coating, Tool C consistently outperformed the others due to its superior protection of the flank face and cutting edge under high-stress conditions. The cutting-induced stresses played a more significant role in the tool wear process than minor differences in workpiece microstructure or tool properties, and a thick CVD coating was most effective in addressing the tool wear effects for the extreme roughing conditions. However, differences in tool life for Tool A showed that tool behavior cannot be predicted based on a single system parameter, even for extreme conditions. Instead, tool properties, workpiece properties, cutting conditions, and their interactions should be considered collectively to evaluate the extent that an individual parameter impacts machinability. This research demonstrates that a comprehensive approach such as this can allow for more effective tool selection and thus lead to significant cost savings and more efficient manufacturing operations. Full article

(This article belongs to the Special Issue Mechanical Properties and Applications for Nanostructured Alloys)

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24 pages, 10552 KiB

Open AccessEditor’s ChoiceReview

Nano-Oncologic Vaccine for Boosting Cancer Immunotherapy: The Horizons in Cancer Treatment

by Chao Chen, Yue Xu, Hui Meng, Hongyi Bao, Yong Hu, Chunjian Li and Donglin Xia

Nanomaterials 2025, 15(2), 122; https://doi.org/10.3390/nano15020122 - 16 Jan 2025

Viewed by 1305

Abstract

Nano-oncologic vaccines represent a groundbreaking approach in the field of cancer immunotherapy, leveraging the unique advantages of nanotechnology to enhance the effectiveness and specificity of cancer treatments. These vaccines utilize nanoscale carriers to deliver tumor-associated antigens and immunostimulatory adjuvants, facilitating targeted immune activation [...] Read more.

Nano-oncologic vaccines represent a groundbreaking approach in the field of cancer immunotherapy, leveraging the unique advantages of nanotechnology to enhance the effectiveness and specificity of cancer treatments. These vaccines utilize nanoscale carriers to deliver tumor-associated antigens and immunostimulatory adjuvants, facilitating targeted immune activation and promoting robust antitumor responses. By improving antigen presentation and localizing immune activation within the tumor microenvironment, nano-oncologic vaccines can significantly increase the efficacy of cancer immunotherapy, particularly when combined with other treatment modalities. This review highlights the mechanisms through which nano-oncologic vaccines operate, their potential to overcome existing limitations in cancer treatment, and ongoing advancements in design. Additionally, it discusses the targeted delivery approach, such as EPR effects, pH response, ultrasonic response, and magnetic response. The combination therapy effects with photothermal therapy, radiotherapy, or immune checkpoint inhibitors are also discussed. Overall, nano-oncologic vaccines hold great promise for changing the landscape of cancer treatment and advancing personalized medicine, paving the way for more effective therapeutic strategies tailored to individual patient needs. Full article

(This article belongs to the Special Issue Applications of Functional Nanomaterials in Biomedical Science)

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13 pages, 5858 KiB

Open AccessEditor’s ChoiceArticle

Temperature Sensing in Agarose/Silk Fibroin Translucent Hydrogels: Preparation of an Environment for Long-Term Observation

by Maria Micheva, Stanislav Baluschev and Katharina Landfester

Nanomaterials 2025, 15(2), 123; https://doi.org/10.3390/nano15020123 - 16 Jan 2025

Viewed by 2764

Abstract

Environmental changes, such as applied medication, nutrient depletion, and accumulation of metabolic residues, affect cell culture activity. The combination of these factors reflects on the local temperature distribution and local oxygen concentration towards the cell culture scaffold. However, determining the temporal variation of [...] Read more.

Environmental changes, such as applied medication, nutrient depletion, and accumulation of metabolic residues, affect cell culture activity. The combination of these factors reflects on the local temperature distribution and local oxygen concentration towards the cell culture scaffold. However, determining the temporal variation of local temperature, independent of local oxygen concentration changes in biological specimens, remains a significant technological challenge. The process of triplet–triplet annihilation upconversion (TTA-UC), performed in a nanoconfined environment with a continuous aqueous phase, appears to be a possible solution to these severe sensing problems. This process generates two optical signals (delayed emitter fluorescence (dF) and residual sensitizer phosphorescence (rPh)) in response to a single external stimulus (local temperature), allowing the application of the ratiometric-type sensing procedure. The ability to incorporate large amounts of sacrificial singlet oxygen scavenging materials, without altering the temperature sensitivity, allows long-term protection against photo-oxidative damage to the sensing moieties. Translucent agarose/silk fibroin hydrogels embedding non-ionic micellar systems containing energetically optimized annihilation couples simultaneously fulfill two critical functions: first, to serve as mechanical support (for further application as a cell culture scaffold); second, to allow tuning of the material response window to achieve a maximum temperature sensitivity better than 0.5 K for the physiologically important region around 36 °C. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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20 pages, 3827 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Two-Dimensional Ferroelectric Materials: From Prediction to Applications

by Shujuan Jiang, Yongwei Wang and Guangping Zheng

Nanomaterials 2025, 15(2), 109; https://doi.org/10.3390/nano15020109 - 12 Jan 2025

Viewed by 1473

Abstract

Ferroelectric materials hold immense potential for diverse applications in sensors, actuators, memory storage, and microelectronics. The discovery of two-dimensional (2D) ferroelectrics, particularly ultrathin compounds with stable crystal structure and room-temperature ferroelectricity, has led to significant advancements in the field. However, challenges such as [...] Read more.

Ferroelectric materials hold immense potential for diverse applications in sensors, actuators, memory storage, and microelectronics. The discovery of two-dimensional (2D) ferroelectrics, particularly ultrathin compounds with stable crystal structure and room-temperature ferroelectricity, has led to significant advancements in the field. However, challenges such as depolarization effects, low Curie temperature, and high energy barriers for polarization reversal remain in the development of 2D ferroelectrics with high performance. In this review, recent progress in the discovery and design of 2D ferroelectric materials is discussed, focusing on their properties, underlying mechanisms, and applications. Based on the work discussed in this review, we look ahead to theoretical prediction for 2D ferroelectric materials and their potential applications, such as the application in nonlinear optics. The progress in theoretical and experimental research could lead to the discovery and design of next-generation nanoelectronic and optoelectronic devices, facilitating the applications of 2D ferroelectric materials in emerging advanced technologies. Full article

(This article belongs to the Special Issue Design of Nanomaterials by Computer Simulation and Artificial Intelligence Approaches (2nd Edition))

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15 pages, 2985 KiB

Open AccessEditor’s ChoiceArticle

‘Ship-in-a-Bottle’ Integration of pH-Sensitive 3D Proteinaceous Meshes into Microfluidic Channels

by Daniela Serien, Koji Sugioka and Aiko Narazaki

Nanomaterials 2025, 15(2), 104; https://doi.org/10.3390/nano15020104 - 10 Jan 2025

Cited by 1 | Viewed by 818

Abstract

Microfluidic sensors incorporated onto chips allow sensor miniaturization and high-throughput analyses for point-of-care or non-clinical analytical tools. Three-dimensional (3D) printing based on femtosecond laser direct writing (fs-LDW) is useful for creating 3D microstructures with high spatial resolution because the structures are printed in [...] Read more.

Microfluidic sensors incorporated onto chips allow sensor miniaturization and high-throughput analyses for point-of-care or non-clinical analytical tools. Three-dimensional (3D) printing based on femtosecond laser direct writing (fs-LDW) is useful for creating 3D microstructures with high spatial resolution because the structures are printed in 3D space along a designated laser light path. High-performance biochips can be fabricated using the ‘ship-in-a-bottle’ integration technique, in which functional microcomponents or biomimetic structures are embedded inside closed microchannels using fs-LDW. Solutions containing protein biomacromolecules as a precursor can be used to fabricate microstructures that retain their native protein functions. Here, we demonstrate the ship-in-a-bottle integration of pure 3D proteinaceous microstructures that exhibit pH sensitivity. We fabricated proteinaceous mesh structures with gap sizes of 10 and 5 μm. The sizes of these gaps changed when exposed to physiological buffers ranging from pH of 4 to 10. The size of the gaps in the mesh can be shrunk and expanded repeatedly by changing the pH of the surrounding buffer. Fs-LDW enables the construction of microscopic proteinaceous meshes that exhibit dynamic functions such as pH sensing and might find applications for filtering particles in microfluidic channels. Full article

(This article belongs to the Section Nanofabrication and Nanomanufacturing)

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