Nanomaterials

17 pages, 7674 KB

Open AccessArticle

Tailoring NiO-Based Nanostructures for the Electrochemical Valorization of Ethanol: Structure–Property Insights

by Ivan Blagojevic, Chiara Maccato, Marta De Zotti, Davide Barreca, Alberto Gasparotto, Raffaella Signorini and Gian Andrea Rizzi

Nanomaterials 2026, 16(8), 496; https://doi.org/10.3390/nano16080496 (registering DOI) - 21 Apr 2026

Abstract

Water electrolysis has emerged as a strategically appealing route for the sustainable production of green hydrogen (H₂) via the hydrogen evolution reaction (HER), though the sluggish kinetics of the oxygen evolution reaction (OER) remains a bottleneck hindering large-scale practical applications. In [...] Read more.

Water electrolysis has emerged as a strategically appealing route for the sustainable production of green hydrogen (H₂) via the hydrogen evolution reaction (HER), though the sluggish kinetics of the oxygen evolution reaction (OER) remains a bottleneck hindering large-scale practical applications. In this regard, an attractive solution is offered by the integration of the ethanol oxidation reaction (EOR) into hybrid water-splitting systems, favorably reducing anodic overpotentials. Nonetheless, an open challenge is related to the fabrication of eco-friendly and economically viable catalysts free from noble metals, combining efficiency and stability. Herein, we explore nickel-oxide-based nanostructures grown onto porous Ni foam scaffolds by a scalable hydrothermal (HT) approach as EOR electrocatalysts. Material properties arising from modulation of the sole HT growth time are investigated by complementary structural, microscopic, and spectroscopic techniques. Electrochemical tests demonstrate good durability and very attractive EOR performances, mainly influenced by the morphology and the NiOOH surface content of the target systems. Overall, the present work advances an attractive route to transition-metal-based electrocatalysts for efficient alcohol-oxidation-assisted water electrolysis. Full article

(This article belongs to the Special Issue The 15th Anniversary of Nanomaterials—Recent Advances in the Synthesis, Interfacial and Structural Properties of Nanosystems)

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19 pages, 7791 KB

Open AccessArticle

Structural, Thermal Behaviour and Tribological Performance in Cold Rolling of Mineral Lubricants with Graphene Nanoplatelets Functionalized with Oleic Acid

by Batuhan Özakın and Kürşat Gültekin

Nanomaterials 2026, 16(8), 495; https://doi.org/10.3390/nano16080495 (registering DOI) - 21 Apr 2026

Abstract

In this study, nanolubricants based on SAE 5W-30 mineral oil were formulated using oleic acid-functionalized graphene nanoplatelets (GNPs), and their colloidal stability, rheological behaviour, thermal stability, and tribological performance under cold rolling conditions were systematically investigated. The nanolubricants were prepared at GNP concentrations [...] Read more.

In this study, nanolubricants based on SAE 5W-30 mineral oil were formulated using oleic acid-functionalized graphene nanoplatelets (GNPs), and their colloidal stability, rheological behaviour, thermal stability, and tribological performance under cold rolling conditions were systematically investigated. The nanolubricants were prepared at GNP concentrations of 0.05, 0.1, 0.2, 0.4, and 0.6 wt%. FT-IR analysis confirmed successful functionalization, evidenced by the characteristic C=O band at approximately 1710 cm⁻¹ and changes in CH₂ stretching vibrations in the 2850–3000 cm⁻¹ range. UV–VIS results indicated initially homogeneous dispersions; however, after three days, relative concentrations decreased to 95%, 90%, and 75% for 0.05, 0.2, and 0.6 wt% GNPs, respectively. Viscosity measurements showed minimal variation at low concentrations, with only a 0.64% increase at 0.2 wt% compared to the base oil. TGA revealed enhanced oxidative stability at low GNP contents, with the oxidation onset temperature increasing from 205.3 °C to 207.2 °C at 0.05 wt%, while a marked decline was observed at higher concentrations (176.8 °C at 0.6 wt%). In cold rolling experiments at a 3% reduction ratio, the rolling force was measured at 1341 N/mm with the neat lubricant, decreasing to 1210 N/mm with a lubricant containing 0.1 wt% GNPs, corresponding to an approximate 10% reduction. Compared with dry conditions, this reduction was approximately 21%. Surface roughness and 3D topography analyses further showed that GNPs-containing lubricants reduced asperities and promoted the formation of a more uniform tribofilm. At low concentrations, the improved lubrication performance of oleic acid-functionalized graphene nanoplatelets is attributed to their homogeneous dispersion in mineral oil, where physically adsorbed oleic acid improves colloidal stability by reducing agglomeration and promotes the formation of a stable tribofilm, facilitating interlayer sliding under boundary lubrication conditions. Overall, the findings demonstrate that oleic acid-functionalized GNPs, when used at optimal concentrations, significantly enhance both lubricant stability and cold rolling performance. Full article

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

15 pages, 1992 KB

Open AccessArticle

Tunable Triple-Band Terahertz Perfect Absorber and Four-Input AND Gate Based on a Graphene Metamaterial

by Shuxin Xu, Lili Zeng, Zhengzheng Shao, Boxun Li, Wenjie Hu, Yiyu Tu and Xingyi Zhu

Nanomaterials 2026, 16(8), 494; https://doi.org/10.3390/nano16080494 (registering DOI) - 21 Apr 2026

Abstract

This study introduces a switchable and tunable multimodal, multi-peak, perfect terahertz absorber, utilizing a composite structure of graphene and double concentric metal rings. From bottom to top, the absorber consists of a gold substrate, a SiO₂ dielectric layer, a patterned graphene layer, [...] Read more.

This study introduces a switchable and tunable multimodal, multi-peak, perfect terahertz absorber, utilizing a composite structure of graphene and double concentric metal rings. From bottom to top, the absorber consists of a gold substrate, a SiO₂ dielectric layer, a patterned graphene layer, another SiO₂ dielectric layer, and double concentric metal rings on the top. The structure achieves three high-absorption resonance peaks in the far-infrared band: a relatively broad peak with 99.05% absorptance at 38.128 THz, and two extremely narrow peaks with 99.56% and 97.23% absorptance at 47.909 THz and 49.873 THz, respectively. Analysis of the absorption spectra and electric field distributions reveals that the generation mechanism of Peak I is Fabry–Pérot cavity resonance, while Peaks II and III result from the coupling between the high-order localized surface plasmons in the outer ring and the graphene surface plasmon polaritons. Benefiting from graphene’s excellent electrical tunability, the absorption peaks’ positions and intensities can be dynamically tuned by varying the Fermi level. The core innovation of this work lies in the high-level integration of multiple functionalities. By leveraging the sensitive response of Peak III to variations in the Fermi level, a four-input AND logic gate is embedded within the metamaterial absorber in this frequency band. The Fermi levels of four independent graphene regions serve as the binary inputs, while the absorption state of Peak III is defined as the logical output. Additionally, the two narrow peaks display high sensitivity to the surrounding refractive index, with sensitivities of 30.1 THz/RIU and 62.5 THz/RIU, demonstrating significant potential for sensing. This multifunctional integrated device combines tunable absorption, a logic gate, and sensing capabilities, making it promising for terahertz communication systems, intelligent sensing networks, and reconfigurable platforms. Full article

(This article belongs to the Special Issue Ultrafast Terahertz Photonics in Nanoscale and Applications)

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17 pages, 2163 KB

Open AccessArticle

Antibacterial Performance of PANI–CdS/Au Nanocomposites Compared to PANI and PANI–CdS

by Raad Al-Kilabi, Abdulameer H. Ali, Hude Al-Allaq, Elias Faraj Mohammed, Sahib Alkulaibi, Adel Alkhayatt, Hussein Al-Shabani, Thmr Ihsan and Haider Al-Hello

Nanomaterials 2026, 16(8), 493; https://doi.org/10.3390/nano16080493 (registering DOI) - 21 Apr 2026

Abstract

Polyaniline-cadmium sulfide-gold (PANI-CdS-Au) nanocomposites were synthesized with varying Au loadings (0.023, 0.046, 0.092 wt%) to enhance antibacterial performance. Structural (FTIR, XRD) and morphological (FESEM) analyses confirmed successful formation, with nearly homogeneous nanoparticle distribution (27–53 nm) and slight XRD peak shifts indicating interfacial interactions [...] Read more.

Polyaniline-cadmium sulfide-gold (PANI-CdS-Au) nanocomposites were synthesized with varying Au loadings (0.023, 0.046, 0.092 wt%) to enhance antibacterial performance. Structural (FTIR, XRD) and morphological (FESEM) analyses confirmed successful formation, with nearly homogeneous nanoparticle distribution (27–53 nm) and slight XRD peak shifts indicating interfacial interactions between PANI, CdS, and Au. UV–Vis spectra revealed gold surface plasmon resonance and polaronic transitions consistent with PANI emeraldine base. XRD results showed the expected wurtzite CdS and fcc Au phases. Agar well diffusion tests against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) demonstrated that the 0.092 wt% of Au composite produced the largest inhibition zones at 100 µg mL⁻¹ (E. coli: 36 mm; S. aureus: 24 mm), with the same trend at 25 µg mL⁻¹. The results indicate that PANI–CdS/Au nanocomposites are promising antibacterial materials; however, the presence of CdS necessitates additional cytotoxicity assays to confirm their suitability for medical applications. Full article

(This article belongs to the Section Nanocomposite Materials)

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19 pages, 10325 KB

Open AccessArticle

Study of PEG/Biochar Cementitious Cold-Bonded Aggregate for Thermal Energy Storage

by Rongji Li, Chong Zhang, Yuechao Zhao, Changliang Wu, Guangbin Duan and Xiuzhi Zhang

Nanomaterials 2026, 16(8), 492; https://doi.org/10.3390/nano16080492 (registering DOI) - 21 Apr 2026

Abstract

The incorporation of phase change materials in concrete is a practical strategy that holds great promise for enhancing the energy efficiency of buildings and reducing CO₂ emissions. However, the direct contact between phase change materials and cement interferes with the cement hydration [...] Read more.

The incorporation of phase change materials in concrete is a practical strategy that holds great promise for enhancing the energy efficiency of buildings and reducing CO₂ emissions. However, the direct contact between phase change materials and cement interferes with the cement hydration reaction, leading to a significant reduction in the mechanical strength of cementitious composites. To encapsulate polyethylene glycol and prevent leakage, this study developed a shape-stabilized phase change aggregate via the cold-bonding method and the vacuum impregnation method. The nanoscale pore structure of the aggregate was regulated by adjusting the biochar content to enhance the phase-change material loading capacity. The phase change aggregate was characterized by indicators including crushing strength and water absorption. Meanwhile, its microstructure, the correlations between nano-sized hydration products, chemical compatibility, and phase change properties were analyzed. The fabricated phase change aggregate has a crushing strength of over 5 MPa, latent heat of 42.84 J/g, and phase change temperature of 29.17 °C while also exhibiting good mechanical properties and thermal energy storage performance. The compressive strength of phase change concrete can meet the strength requirements for structural building material. Moreover, phase change aggregate contributed to reduced CO₂ emissions during service, with favorable economic and low-carbon benefits over its service life, demonstrating good performance in both economic efficiency and CO₂ emission reduction. Full article

(This article belongs to the Special Issue Nanocomposite Modified Cement and Concrete)

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19 pages, 4707 KB

Open AccessArticle

Liquid-Phase Synthesis and Regulatory Mechanisms of Nano-Nickel Powders for MLCC Inner Electrodes

by Zhenzong Quan, Jianwei Wang, Huijun He, Xingming Wang, Liqing Ban, Xiaoling Ma and Haijun Zhao

Nanomaterials 2026, 16(8), 491; https://doi.org/10.3390/nano16080491 (registering DOI) - 21 Apr 2026

Abstract

Driven by the demand for miniaturization, high capacitance, and enhanced reliability in high-performance multilayer ceramic capacitors (MLCCs), the continuous thinning of inner electrode layers imposes increasingly stringent requirements on the size, distribution, morphology, and dispersion of nano-nickel powders. We systematically investigate how functional [...] Read more.

Driven by the demand for miniaturization, high capacitance, and enhanced reliability in high-performance multilayer ceramic capacitors (MLCCs), the continuous thinning of inner electrode layers imposes increasingly stringent requirements on the size, distribution, morphology, and dispersion of nano-nickel powders. We systematically investigate how functional additives regulate the nucleation, growth, and microstructural evolution of nano-nickel synthesized via hydrazine-driven liquid-phase reduction of nickel sulfate. The results demonstrate that the alkanolamine complexing agent (TAC) significantly refines the average particle size and morphology of the nano-nickel through coordination effects. Furthermore, inorganic sulfur salts (ISP), acting via surface adsorption to passivate growth sites and provide catalytic effects, enable a precise and continuous reduction in the average particle diameter from 330 nm down to 60 nm at a mere trace dosage of ~10⁻⁷ mol/L. Regarding dispersion optimization, highly dispersed face-centered cubic (FCC) nano-nickel was successfully prepared by introducing multidentate carboxylate (NNA). High-resolution transmission electron microscopy (HRTEM) was employed to unveil, for the first time, the crystallographic origin of the anomalous surface protrusions typically observed in conventional reaction systems. We confirmed that the family of

\{10 \bar{1} 0\}

crystal planes within these regions, which exhibits interfacial angles of 58.7° and 58.3°, corresponds to a thermodynamically metastable hexagonal close-packed (HCP) nickel phase originating from atomic stacking faults induced by rapid growth kinetics. To address this microstructural defect, a thioether-based amino acid (TAA) was introduced. TAA effectively suppresses the anisotropic growth of the metastable HCP phase through the strong steric hindrance of its long side chains and its selective adsorption onto high-energy facets. Full article

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

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15 pages, 4902 KB

Open AccessArticle

VO₂–Graphene Terahertz Multifunctional Metasurface with Switchable Broadband Waveplates and Absorber

by Hong Su, Tao Huang, Gaozhao Liu, Wentao Chen, Jiarong Zi, Chenglong Zhang, Shiping Feng, Min Zhang, Ling Li, Huawei Liang and Shixing Wang

Nanomaterials 2026, 16(8), 490; https://doi.org/10.3390/nano16080490 - 20 Apr 2026

Abstract

A terahertz multifunctional metasurface based on vanadium dioxide (VO₂) and graphene that can switch between waveplate and absorber functionalities is proposed. As the temperature is below 300 K, by electrically controlling the Femi energy of the graphene it can realize half-wave [...] Read more.

A terahertz multifunctional metasurface based on vanadium dioxide (VO₂) and graphene that can switch between waveplate and absorber functionalities is proposed. As the temperature is below 300 K, by electrically controlling the Femi energy of the graphene it can realize half-wave plate (HWP) and quarter-wave plate (QWP) functionalities in the operating bandwidths of both 1.39–2.34 THz and 0.92–2.68 THz, respectively. While the temperature is above 340 K, the dipole resonance between VO₂ and a gold reflector induces absorption. Furthermore, by applying the voltage to graphene, dual-parameter modulation of the amplitude of the transverse electric (TE) waves and the resonance frequency of the transverse magnetic (TM) waves is achieved, the absorption bandwidths of which are 3.65–3.78 THz and 1.41–3.12 THz, respectively. The operating frequencies for HWP, QWP, TE and TM waves can be tuned by changing the electrical field and working temperature. In addition, the incident angles are not sensitive to the performance of the metasurface, confirming its effectiveness even under large-angle incidence. The metasurface with simplicity in design, mature fabrication processes, and comprehensive functionality, has certain promising applications in terahertz optical switches, terahertz spectroscopy systems, modulators, and communication systems. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

13 pages, 6812 KB

Open AccessArticle

Green Supercritical CO₂ Ion-Exchange Strategy for Cation Engineering in Polyheptazine Imides Towards Efficient Photoreduction CO₂ to C₂H₄

by Xin Peng, Lina Du, Gaoliang Fu, Shouren Zhang and Junying Ma

Nanomaterials 2026, 16(8), 489; https://doi.org/10.3390/nano16080489 - 20 Apr 2026

Abstract

Photocatalytic reduction of carbon dioxide (CO₂) into high-value multicarbon products, such as ethylene (C₂H₄), remains a significant challenge due to the difficult C-C coupling process. Potassium poly(heptazine imide) (K-PHI) is a promising photocatalyst, yet efficiently exchanging its [...] Read more.

Photocatalytic reduction of carbon dioxide (CO₂) into high-value multicarbon products, such as ethylene (C₂H₄), remains a significant challenge due to the difficult C-C coupling process. Potassium poly(heptazine imide) (K-PHI) is a promising photocatalyst, yet efficiently exchanging its interlayer cations to tune catalytic selectivity without causing structural degradation is difficult. Herein, an efficient and green supercritical CO₂ (SC CO₂) assisted ion-exchange strategy was developed to successfully prepare a series of mono-/di-/trivalent cation-doped M-PHI photocatalysts (M = H⁺, Na⁺, Sr⁺, Ca²⁺, Co²⁺, Fe³⁺). Systematic characterizations confirmed that the SC-CO₂ treatment successfully achieved in-depth cation substitution without destroying the intrinsic heptazine framework, effectively regulating the interlayer structure and significantly optimizing the photoelectrochemical charge separation. Among the prepared samples, H-PHI exhibited the optimal photocatalytic CO₂ reduction performance with an outstanding selectivity toward C₂H₄ generation. Under simulated sunlight irradiation for 3 h, the yields of CO, CH₄, and C₂H₄ C₂H₄ C₂H₄ reached 3564.87, 807.32, and 40.00 μmol·g⁻¹, respectively, significantly outperforming pristine K-PHI and other metal-doped samples. Crucially, isotope-tracing experiments utilizing a SC CO₂-DCl treatment detected deuterated CH₄ and C₂H₄ products, providing direct evidence that the hydrogen in the carbon products originates from the introduced protons, thereby elucidating the precise reaction pathway for C-C coupling. This study provides a green and efficient supercritical CO₂ ion exchange strategy for the cation engineering of crystalline carbon nitride, and also offers new ideas and methods for designing high-activity photocatalysts for photocatalytic CO₂ reduction. Full article

(This article belongs to the Section Energy and Catalysis)

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28 pages, 7815 KB

Open AccessReview

Carbon Dots for Corrosion Protection: A Systematic Review of Applications and Mechanisms

by Xiaochuan Liu, Jinlin Li, Shengbin Li, Chuang He and Haijie He

Nanomaterials 2026, 16(8), 488; https://doi.org/10.3390/nano16080488 - 20 Apr 2026

Abstract

Carbon dots (CDs) have demonstrated promising application prospects in the field of corrosion protection due to their small size, excellent dispersibility, abundant and tunable surface functional groups, low cost, environmental friendliness, and unique fluorescence properties. However, existing reviews have predominantly focused on the [...] Read more.

Carbon dots (CDs) have demonstrated promising application prospects in the field of corrosion protection due to their small size, excellent dispersibility, abundant and tunable surface functional groups, low cost, environmental friendliness, and unique fluorescence properties. However, existing reviews have predominantly focused on the synthesis and photoluminescence properties of CDs, lacking systematic integration and in-depth mechanistic analysis of their diverse applications in corrosion protection. This review systematically summarizes the recent research progress and underlying mechanisms of CDs in five key areas: corrosion inhibitors, anticorrosive coatings, photogenerated cathodic protection, chloride binding, and corrosion monitoring. As corrosion inhibitors, CDs form compact protective films on metal surfaces through synergistic physical and chemical adsorption. In anticorrosive coatings, CDs not only enhance the physical barrier effect but also impart intelligent functionalities such as self-healing and corrosion monitoring. In the field of photogenerated cathodic protection, CDs broaden the light absorption range of semiconductors and facilitate the separation of photogenerated carriers. As chloride binding promoters, CDs promote the formation of cement hydration products, thereby improving the durability of reinforced concrete structures. As sensing platforms, CDs enable early visual detection of corrosion through their specific fluorescence response to ions such as Fe³⁺. Despite significant progress, challenges remain in scalable preparation, practical application performance in complex environments, and multifunctional integration. This review systematically outlines the research advancements of CDs in corrosion protection, providing a practical reference for subsequent studies and engineering applications. Future research should focus on scalable synthesis, machine learning-assisted design, and the development of integrated multifunctional protection systems to promote the practical application of CDs in the field of corrosion protection. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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17 pages, 3696 KB

Open AccessArticle

Rheological and Physicochemical Properties Following Ageing of a Graphene-Based Nanomaterial Under Development as Surgical Implant

by Amelia Seifalian, Alex Digesu and Vikram Khullar

Nanomaterials 2026, 16(8), 487; https://doi.org/10.3390/nano16080487 - 19 Apr 2026

Abstract

A novel graphene-based nanomaterial, trade registered Hastalex^®, has been synthesised and investigated for its application as a 3D scaffold in surgical implantation. Hastalex is developed through the covalent bonding of amine-group-functionalised graphene oxide to the base chemical, poly(carbonate-urea)urethane. The material is [...] Read more.

A novel graphene-based nanomaterial, trade registered Hastalex^®, has been synthesised and investigated for its application as a 3D scaffold in surgical implantation. Hastalex is developed through the covalent bonding of amine-group-functionalised graphene oxide to the base chemical, poly(carbonate-urea)urethane. The material is under development for medical application including tendon, heart valve, and pelvic implant for prolapse surgery. For successful clinical translation, long-term rheological and chemical stability must be demonstrated and until now no systematic multi-year evaluation has been reported for graphene-poly(carbonate-urea)urethane nanocomposites. The material was synthesised in accordance with the patented formulation and evaluated at 0, 6, 12, and 24 months post-synthesis. Physicochemical properties were assessed using attenuated total reflectance Fourier-transform infrared spectroscopy, scanning electron microscope, contact angle measurements, thermogravimetric analysis, and mechanical analysis with tensile tests. Flow behaviour of Hastalex was evaluated using a rheometer to determine viscosity, shear stress response and impact of temperature changes and ageing on these factors. Hastalex exhibited non-Newtonian, shear-thinning behaviour consistent across all timepoints. Viscosity was found to increase progressively with ageing, attributed not to chemical degradation, but likely due to gradual solvent evaporation and densification of the polymer matrix during storage under ambient conditions. Rheological measurements across increasing temperature regimes revealed a heat-sensitive decrease in viscosity, followed by a reversal of changes beyond ~80 °C—likely due to enhanced solvent evaporation and chain reorganisation. This comprehensive material characterisation supports Hastalex as a promising candidate for bioengineering applications. Full article

(This article belongs to the Special Issue Nanomaterials and Energetics: Design, Developments, and Challenges from Experimentation and Computation Aspects)

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15 pages, 1747 KB

Open AccessArticle

Controlled Plasmonic Coupling in Silver Nanoplate Dimers for Enhanced Plasmonic Sensing

by Lucrezia Catanzaro, Marcello Condorelli, Mario Pulvirenti, Luisa D’urso and Giuseppe Compagnini

Nanomaterials 2026, 16(8), 486; https://doi.org/10.3390/nano16080486 - 19 Apr 2026

Abstract

Noble metal nanostructures provide versatile platforms for light manipulation through localized surface plasmon resonances (LSPRs). Among them, triangular silver nanoplates (AgNPTs) exhibit strong field-enhancement and spectral tunability, yet assembling them reproducibly on solids is challenging. We report a two-step functionalization strategy for constructing [...] Read more.

Noble metal nanostructures provide versatile platforms for light manipulation through localized surface plasmon resonances (LSPRs). Among them, triangular silver nanoplates (AgNPTs) exhibit strong field-enhancement and spectral tunability, yet assembling them reproducibly on solids is challenging. We report a two-step functionalization strategy for constructing ordered AgNPT dimers on silica substrates, combining 3-aminopropyltriethoxysilane (APTES) anchoring with 1,4-butanedithiol bridging. AFM reveals face-to-face dimers with well-defined sub-nanometer gaps. Large-area AFM statistics collected over multiple regions (N = 80 nanoplates per condition) confirm reproducible and selective vertical dimerization. Extinction spectroscopy reveals sequential dielectric and coupling effects: thiol adsorption red-shifts the main resonance from 700 to 780 nm because of increased local refractive index and near-field damping, whereas dimerization partially restores it to ≈750 nm, consistent with plasmon hybridization within rigid ∼0.7 nm molecular gaps, where nonclassical moderation may occur but classical hybridization fully explains the observed shifts. Concomitantly, the extinction intensity doubles, following an exponential growth toward saturation during assembly. Surface-enhanced Raman scattering (SERS) measurements using 4-mercaptobenzoic acid (4-MBA) confirm a fourfold increase in the SERS enhancement factor from monolayer to bilayer, consistent with near-field coupling and hotspot formation at interplate junctions. Quantitative plasmon sensitivity analysis yields comparable results between experiments and finite-difference-time-domain simulations, confirming that the observed spectral shifts arise from near-field coupling and dielectric modulation rather than ensemble effects. This reproducible methodology enables precise tuning of NPT orientation, spacing, and optical response, providing a robust platform for enhanced sensing, SERS, and nanophotonic device engineering. Full article

(This article belongs to the Topic Functional Materials for Chemical Sensing and Environmental Sustainability: Trends, Concepts and Applications)

18 pages, 3396 KB

Open AccessArticle

Fabrication of Nitrogen-Containing Micro-Expanding Graphite Composites from Waste Graphite Electrodes for Enhanced Lithium Storage

by Xu Fan, Zhuohan Lv, Hongyan Nan, Daoguang Teng, Baolin Xing and Peng Li

Nanomaterials 2026, 16(8), 485; https://doi.org/10.3390/nano16080485 - 19 Apr 2026

Abstract

The large-scale generation of waste graphite not only poses environmental challenges but also provides an opportunity for resource recovery. This study proposes a sustainable strategy that utilizes the graphite cutting waste produced during the production of large graphite electrodes through chemical intercalation, microwave-assisted [...] Read more.

The large-scale generation of waste graphite not only poses environmental challenges but also provides an opportunity for resource recovery. This study proposes a sustainable strategy that utilizes the graphite cutting waste produced during the production of large graphite electrodes through chemical intercalation, microwave-assisted expansion, and in situ urea nitrogen doping techniques to prepare nitrogen-containing micro-expanded graphite (NMG) composite materials. Structural analysis reveals that the nitrogen-doped amorphous carbon layer formed on the expanded graphite (EG) matrix effectively suppresses excessive expansion while preserving its typical worm-like interlayer morphology and porous structure. XPS confirms successful nitrogen doping with predominant pyridinic-N configuration, introducing abundant defect sites and enhancing lithiophilicity. As an anode for LIBs, NMG delivers an exceptional initial discharge capacity of 1907.5 mAh g⁻¹ at 20 mA g⁻¹ and maintains 798.2 mAh g⁻¹ after 50 cycles, nearly twice that of purified waste graphite (G). Remarkably, after 1000 cycles at 1 A g⁻¹, it retains 650.4 mAh g⁻¹ with 89.9% capacity retention, indicating an electrochemical activation process. Kinetic analysis reveals that the superior performance originates from synergistic diffusion-controlled intercalation and surface-dominated pseudocapacitance, with nitrogen-doped defect sites and hierarchical pore architecture promoting rapid ion/electron transport and surface faradaic reactions. This work demonstrates a viable pathway for value-added upcycling of waste graphite while providing insights into designing high-performance anodes through integrated defect engineering and heteroatom doping. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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13 pages, 3360 KB

Open AccessArticle

Synergistic Enhancement of Visible-Light-Driven Photocatalytic H₂O₂ Production over g-C₃N₄/ZnCdS by Zn Vacancies and Heterointerface Engineering

by Zhenyu Wang, Wei Yan, Yingcong Wei, Jing Xu, Yuee Xie, Yuanping Chen and Xiaohong Yan

Nanomaterials 2026, 16(8), 484; https://doi.org/10.3390/nano16080484 - 18 Apr 2026

Abstract

Hydrogen peroxide (H₂O₂) is an important green oxidant, and developing efficient visible-light-driven routes for its synthesis is highly desirable. Herein, a CN/Zn_V-ZCS composite photocatalyst was constructed by coupling g-C₃N₄ (CN) with Zn-vacancy-containing ZnCdS (Zn [...] Read more.

Hydrogen peroxide (H₂O₂) is an important green oxidant, and developing efficient visible-light-driven routes for its synthesis is highly desirable. Herein, a CN/Zn_V-ZCS composite photocatalyst was constructed by coupling g-C₃N₄ (CN) with Zn-vacancy-containing ZnCdS (Zn_V-ZCS) for photocatalytic H₂O₂ production. The optimized CN/Zn_V-10 delivered 44.58 mmol g⁻¹ H₂O₂ within 60 min under 425 nm LED irradiation, outperforming pristine CN, ZCS, Zn_V-ZCS, and vacancy-free CN/ZCS, with good cycling stability. Trapping and EPR results identify O₂ as the key electron acceptor and ·O₂⁻ as an important intermediate. Structural characterization and XPS results indicate successful Zn-vacancy introduction, intimate heterointerface formation, and interfacial electron redistribution. Combined VB-XPS, photoelectrochemical, and reactive-species analyses suggest that Zn vacancies are favorable for O₂ adsorption/activation, whereas the CN/Zn_V-ZCS heterointerface promotes charge separation and migration. Based on the available evidence, a Z-scheme interfacial charge-transfer pathway is established in the CN/Zn_V-ZCS system. Full article

(This article belongs to the Section Energy and Catalysis)

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21 pages, 988 KB

Open AccessReview

Ayurvedic Medicinal Plants and Plant-Derived Extracellular Vesicles: Current Evidence and Future Perspectives

by Manasi Bhabal, Tiziana Pietrangelo, Mariantonia Logozzi and Stefano Fais

Nanomaterials 2026, 16(8), 483; https://doi.org/10.3390/nano16080483 - 18 Apr 2026

Abstract

Plant-derived extracellular vesicles (PDEVs) are nanoscale carriers produced through conserved plant mechanisms, including multivesicular body (MVB) formation and consequent extracellular vesicle release. MVBs are formed through repeated rounds of intracellular vesicles’ fusion, thus leading to the incorporation into PDEVs of lipids, proteins, miRNAs, [...] Read more.

Plant-derived extracellular vesicles (PDEVs) are nanoscale carriers produced through conserved plant mechanisms, including multivesicular body (MVB) formation and consequent extracellular vesicle release. MVBs are formed through repeated rounds of intracellular vesicles’ fusion, thus leading to the incorporation into PDEVs of lipids, proteins, miRNAs, nucleic acids, and secondary metabolites, derived from different cellular compartments. PDEVs possess a bilayer lipid membrane, which protects their cargo from degradation and facilitates membrane–membrane fusion with target cells. Ayurvedic medicinal plants are renowned for their extensive phytochemical diversity and enduring efficacy in addressing inflammation, infections, metabolic disorders, cancer, and neurodegeneration. However, the clinical translation of traditional herbal preparation is severely bottlenecked by batch-to-batch variability, restricted compound bioavailability, mechanistic uncertainties, and limitations of conventional large-scale extractions. This perspective research study critically proposes PDEVs as an innovative interpretation for Ayurvedic medicinal plants utilization. We identify and evaluate medicinal plants with established therapeutic characteristics that remain unexamined in PDEV research, hence presenting compelling opportunities for future investigation. By establishing a synergistic bridge between ancient Ayurvedic knowledge and modern nanomedicine, this perspective provides a methodological roadmap to guide health-efficient plant selection and accelerate translational research in next-generation therapeutics. Full article

(This article belongs to the Section Biology and Medicines)

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14 pages, 6208 KB

Open AccessArticle

Rhodamine B Dye-Functionalized Hydrophobic Carbon Quantum Dots with Dual Emission for White-Light Organic Optoelectronic Devices

by Walaa Al-Masri and Alaa Y. Mahmoud

Nanomaterials 2026, 16(8), 482; https://doi.org/10.3390/nano16080482 - 18 Apr 2026

Abstract

Hydrophobic carbon quantum dots (hbCQDs) with tunable photoluminescence were synthesized via a solvothermal approach and further hybridized with Rhodamine B (RhB) to extend emission into the visible range. The hbCQDs exhibit quasi-spherical morphology with an average particle size of 8 nm and predominantly [...] Read more.

Hydrophobic carbon quantum dots (hbCQDs) with tunable photoluminescence were synthesized via a solvothermal approach and further hybridized with Rhodamine B (RhB) to extend emission into the visible range. The hbCQDs exhibit quasi-spherical morphology with an average particle size of 8 nm and predominantly disordered graphitic structure, as confirmed by TEM and XRD analyses. FTIR and XPS characterizations reveal surface functional groups including C–N, C=O/C–O, and S–H, which govern the photoluminescence properties. Pure hbCQDs display blue emission at 453 nm under excitation, with a quantum yield (QY) of 6.2%. Incorporation of RhB leads to dual-emission behavior: the surface-state emission remains in the blue region, while molecular-state emission from RhB appears in the orange-red region. The 0.2 mL RhB–CQD composite exhibits optimal properties, including a QY of 13% and a production yield of 82%, emitting white light under 365 nm UV excitation. Increasing RhB loading to 0.4 mL results in a shift in emission peaks and a reduced QY (<9%), with weaker orange fluorescence. These findings demonstrate that controlled RhB hybridization effectively tunes the emission spectrum of hbCQDs, offering a simple and reproducible strategy to achieve dual-color and white-light emission. The optimized hbCQDs/RhB composites hold significant potential for applications in hydrophobic media-compatible organic optoelectronics, light-emitting devices, and bioimaging. Full article

(This article belongs to the Special Issue Photothermal Nanomaterials: Synthesis, Properties and Applications)

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13 pages, 1222 KB

Open AccessArticle

Research on Superconductivity in Multilayer ABC-Stacked Graphene

by Jun-liang Wang, Jia-xue Liang and Xiu-qing Wang

Nanomaterials 2026, 16(8), 481; https://doi.org/10.3390/nano16080481 - 17 Apr 2026

Abstract

Under the deformation potential model, the superconducting phenomenon in ABC-stacked multilayer graphene under a vertical electric field is investigated using linear combination operators and unitary transformation methods. Through the deformation potential model applied to a linear continuous medium, the effect of the external [...] Read more.

Under the deformation potential model, the superconducting phenomenon in ABC-stacked multilayer graphene under a vertical electric field is investigated using linear combination operators and unitary transformation methods. Through the deformation potential model applied to a linear continuous medium, the effect of the external electric field is converted into the deformation potential energy of the crystal. Deformation potential phonons (LA phonons) act as propagators, generating electron–electron interactions. As the electric field increases, the ratio of the electric displacement vector to the dielectric function (D/ε) rises, leading to an increase in the electron ground-state energy, the opening of the band gap, and an enhancement of the attractive electron–electron interaction. With further increases in the external electric field, the deformation potential constant of the crystal (D_l) increases. When the phonon vibration frequency (ω) is around 8.5 THz, and the conditions are satisfied—where the wave vectors of different LA phonons are equal in magnitude and opposite in direction, and the electron spins are opposite—the attractive electron–electron interaction reaches its maximum (H_ceff), resulting in the emergence of superconductivity. Our study also provides a new perspective for understanding the unique quantum properties—such as strong correlations, superconductivity, and ferromagnetism—in different stacking configurations like AB, ABC, and ABCA. Full article

(This article belongs to the Special Issue Nanoscale Phenomena of 2D Material Heterostructures)

10 pages, 2420 KB

Open AccessArticle

Performance Investigation of AlGaInP Light-Emitting Diodes

by Weiwei Sun, Shaobo Ge, Junyan Li, Lujun Shen, Xinyu Zhao, Ronghua Shi, Jin Zhang and Yingxue Xi

Nanomaterials 2026, 16(8), 480; https://doi.org/10.3390/nano16080480 - 17 Apr 2026

Abstract

Previous studies have shown that the external quantum efficiency (EQE) of conventional red Micro-Light emitting diodes(Micro-LEDs) decreases markedly with reducing chip size. This degradation is generally attributed to enhanced non-radiative recombination at sidewall defects, which leads to increased carrier loss in size-scaled LEDs. [...] Read more.

Previous studies have shown that the external quantum efficiency (EQE) of conventional red Micro-Light emitting diodes(Micro-LEDs) decreases markedly with reducing chip size. This degradation is generally attributed to enhanced non-radiative recombination at sidewall defects, which leads to increased carrier loss in size-scaled LEDs. In this work, AlGaInP quaternary semiconductor epitaxial wafers incorporating multiple quantum wells (MQWs) with different well-layer strain states were grown by metal–organic chemical vapor deposition (MOCVD). Through wafer bonding, photolithography, etching, and metal evaporation, these epitaxial structures were fabricated into Micro-LED arrays with single-pixel pitches of 10, 20, 50, and 100 μm. The experimental results reveal that, with increasing indium (In) composition in the GaInP well layers—corresponding to a gradual increase in lattice mismatch (Δa/a) from 0% to 1%—smaller-sized Micro-LED arrays exhibit superior EQE performance. For devices with a pixel pitch of 10 μm, the EQE of Micro-LED arrays with a 1% lattice mismatch in the well layer is approximately three times higher than that of lattice-matched (0%) counterparts. In contrast, for devices with a pixel pitch of 100 μm, the EQE of lattice-matched (0%) Micro-LED arrays is about 1.3 times higher than that of devices with a 1% lattice mismatch. These results indicate that, to achieve maximum EQE in Micro-LEDs, the strain state of the MQW-layer material must be carefully considered as a priority factor. Optimal device performance requires appropriate matching between LED size and the well-layer growth strain. Full article

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

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16 pages, 7051 KB

Open AccessArticle

One-Step Immunoassay of Alpha-Fetoprotein Constructed by Silicon-Quantum-Dot-Loaded Porous Gold Nanoshells

by Xiaoling Lu, Chao Shen, You Long, Song Zhang, Fang Chen, Nan Chen and Chenghong Huang

Nanomaterials 2026, 16(8), 479; https://doi.org/10.3390/nano16080479 - 17 Apr 2026

Abstract

Alpha-fetoprotein (AFP) is widely utilized for auxiliary diagnosis of primary hepatocellular carcinoma. Therefore, the development of a facile immunosensor is essential for clinical applications. This study aims to develop a simple immunoassay for AFP detection. By incorporating silicon quantum dots (SiQDs) into etching [...] Read more.

Alpha-fetoprotein (AFP) is widely utilized for auxiliary diagnosis of primary hepatocellular carcinoma. Therefore, the development of a facile immunosensor is essential for clinical applications. This study aims to develop a simple immunoassay for AFP detection. By incorporating silicon quantum dots (SiQDs) into etching hollow gold nanoshells (EHGNs) via precise nanomanipulation, we designed molecular probes based on SiQDs@EHGNs complex immobilized capture antibodies, which can convert the antigen/antibody binding process into fluorescent divergence signals for AFP measurement. This strategy enabled one-step fluorescence sensing for AFP detection with a linear range of 3.125–200.0 ng/mL and LOD of 0.234 ng/mL. The detection results of 15 clinical serum real samples demonstrated a 93.7% correlation with the market-accepted ECLIA method. The proposed method take advantages of simplicity and rapid response, offering a novel approach for tumor marker analysis with significant potential. Full article

(This article belongs to the Special Issue Carbon Quantum Dots (CQDs) and Related Systems)

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23 pages, 6333 KB

Open AccessArticle

Prediction of Composite Supercapacitor Performance Through Combining Machine Learning with Novel Binder-Related Features

by Tianshun Gong, Weiyang Yu and Xiangfu Wang

Nanomaterials 2026, 16(8), 478; https://doi.org/10.3390/nano16080478 - 17 Apr 2026

Abstract

The development of high-performance composite supercapacitors remains challenging because the specific capacitance of composite electrodes is jointly governed by electronic percolation, ion accessibility, and interfacial contact, all of which are strongly affected by the balance among active materials, conductive agents, and binders. Traditional [...] Read more.

The development of high-performance composite supercapacitors remains challenging because the specific capacitance of composite electrodes is jointly governed by electronic percolation, ion accessibility, and interfacial contact, all of which are strongly affected by the balance among active materials, conductive agents, and binders. Traditional equivalent circuit modeling and empirical trial-and-error methods are often inadequate for describing these non-linear relationships and optimizing electrode design. To address this limitation, we establish a physics-guided and interpretable machine learning (ML) framework for predicting the specific capacitance of composite electrodes. Unlike traditional methods that rely on macroscopic mass fractions, our approach constructs a feature space comprising ten descriptors, including two newly introduced binder-related proxy descriptors—Binder-to-Conductive Ratio (BCR) and Specific Binder Loading (SBL)—to better represent the influence of binder content. By systematically evaluating 17 machine learning algorithms on a high-fidelity dataset, we identify the XGBoost model, optimized via Bayesian optimization, as the best predictor, achieving a coefficient of determination (R²) of 0.981 and a low mean absolute percentage error (MAPE) of 14.49%. Importantly, interpretability analysis using Shapley Additive Explanations (SHAP) provides physically interpretable statistical insights, revealing that high BCR suppresses specific capacitance through an insulating barrier effect, whereas lattice distortion in the filler material promotes ion transport. This study offers a robust, data-driven framework for optimizing composite electrode performance, demonstrating the potential of interpretable ML models for the rational design of advanced energy-storage materials. Full article

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

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