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Nanomaterials, Volume 9, Issue 10 (October 2019)

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Open AccessArticle
Influence of Titanium Oxide Pillar Array Nanometric Structures and Ultraviolet Irradiation on the Properties of the Surface of Dental Implants—A Pilot Study
Nanomaterials 2019, 9(10), 1458; https://doi.org/10.3390/nano9101458 (registering DOI) - 14 Oct 2019
Abstract
Aim: Titanium implants are commonly used as replacement therapy for lost teeth and much current research is focusing on the improvement of the chemical and physical properties of their surfaces in order to improve the osseointegration process. TiO2, when it is [...] Read more.
Aim: Titanium implants are commonly used as replacement therapy for lost teeth and much current research is focusing on the improvement of the chemical and physical properties of their surfaces in order to improve the osseointegration process. TiO2, when it is deposited in the form of pillar array nanometric structures, has photocatalytic properties and wet surface control, which, together with UV irradiation, provide it with superhydrophilic surfaces, which may be of interest for improving cell adhesion on the peri-implant surface. In this article, we address the influence of this type of surface treatment on type IV and type V titanium discs on their surface energy and cell growth on them. Materials and methods: Samples from titanium rods used for making dental implants were used. There were two types of samples: grade IV and grade V. In turn, within each grade, two types of samples were differentiated: untreated and treated with sand blasting and subjected to double acid etching. Synthesis of the film consisting of titanium oxide pillar array structures was carried out using plasma-enhanced chemical vapor deposition equipment. The plasma was generated in a quartz vessel by an external SLAN-1 microwave source with a frequency of 2.45 GHz. Five specimens from each group were used (40 discs in total). On the surfaces to be studied, the following determinations were carried out: (a) X-ray photoelectron spectroscopy, (b) scanning electron microscopy, (c) energy dispersive X-ray spectroscopy, (d) profilometry, (e) contact angle measurement or surface wettability, (f) progression of contact angle on applying ultraviolet irradiation, and (g) a biocompatibility test and cytotoxicity with cell cultures. Results: The application of ultraviolet light decreased the hydrophobicity of all the surfaces studied, although it did so to a greater extent on the surfaces with the studied modification applied, this being more evident in samples manufactured in grade V titanium. In samples made in grade IV titanium, this difference was less evident, and even in the sample manufactured with grade IV and SLA treatment, the application of the nanometric modification of the surface made the surface optically less active. Regarding cell growth, all the surfaces studied, grouped in relation to the presence or not of the nanometric treatment, showed similar growth. Conclusions. Treatment of titanium oxide surfaces with ultraviolet irradiation made them change temporarily into superhydrophilic ones, which confirms that their biocompatibility could be improved in this way, or at least be maintained. Full article
Open AccessArticle
Experimental Evaluation on the Heating Efficiency of Magnetoferritin Nanoparticles in an Alternating Magnetic Field
Nanomaterials 2019, 9(10), 1457; https://doi.org/10.3390/nano9101457 (registering DOI) - 14 Oct 2019
Abstract
The superparamagnetic substance magnetoferritin is a potential bio-nanomaterial for tumor magnetic hyperthermia because of its active tumor-targeting outer protein shell, uniform and tunable nanosized inner mineral core, monodispersity and good biocompatibility. Here, we evaluated the heating efficiency of magnetoferritin nanoparticles in an alternating [...] Read more.
The superparamagnetic substance magnetoferritin is a potential bio-nanomaterial for tumor magnetic hyperthermia because of its active tumor-targeting outer protein shell, uniform and tunable nanosized inner mineral core, monodispersity and good biocompatibility. Here, we evaluated the heating efficiency of magnetoferritin nanoparticles in an alternating magnetic field (AMF). The effects of core-size, Fe concentration, viscosity, and field frequency and amplitude were investigated. Under 805.5 kHz and 19.5 kA/m, temperature rise (ΔT) and specific loss power (SLP) measured on magnetoferritin nanoparticles with core size of 4.8 nm at 5 mg/mL were 14.2 °C (at 6 min) and 68.6 W/g, respectively. The SLP increased with core-size, Fe concentration, AMF frequency, and amplitude. Given that: (1) the SLP was insensitive to viscosity of glycerol-water solutions and (2) both the calculated effective relaxation time and the fitted relaxation time were closer to Néel relaxation time, we propose that the heating generation mechanism of magnetoferritin nanoparticles is dominated by the Néel relaxation. This work provides new insights into the heating efficiency of magnetoferritin and potential future applications for tumor magnetic hyperthermia treatment and heat-triggered drug release. Full article
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Open AccessArticle
Direct Growth of Two Dimensional Molybdenum Disulfide on Flexible Ceramic Substrate
Nanomaterials 2019, 9(10), 1456; https://doi.org/10.3390/nano9101456 (registering DOI) - 14 Oct 2019
Abstract
In this paper, we report the first successful demonstration of the direct growth of high-quality two-dimensional (2D) MoS2 semiconductors on a flexible substrate using a 25-m-thick Yttria-stabilized zirconia ceramic substrate. Few-layered MoS2 crystals grown at 800 °C showed a uniform crystal [...] Read more.
In this paper, we report the first successful demonstration of the direct growth of high-quality two-dimensional (2D) MoS2 semiconductors on a flexible substrate using a 25-m-thick Yttria-stabilized zirconia ceramic substrate. Few-layered MoS2 crystals grown at 800 °C showed a uniform crystal size of approximately 50 m, which consisted of about 10 MoS2 layers. MoS2 crystals were characterized using energy-dispersive X-ray spectroscopy. Raman spectroscopy was performed to investigate the crystal quality under bending conditions. The Raman mapping revealed a good uniformity with a stable chemical composition of the MoS2 crystals. Our approach offers a simple and effective route to realize various flexible electronics based on MoS2. Our approach can be applied for MoS2 growth and for other 2D materials. Therefore, it offers a new opportunity that allows us to demonstrate high-performance flexible electronic/optoelectronic applications in a less expensive, simpler, and faster manner without sacrificing the intrinsic performance of 2D materials. Full article
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Open AccessReview
Emergent Nanotechnological Strategies for Systemic Chemotherapy against Melanoma
Nanomaterials 2019, 9(10), 1455; https://doi.org/10.3390/nano9101455 - 13 Oct 2019
Viewed by 118
Abstract
Melanoma is an aggressive form of skin cancer, being one of the deadliest cancers in the world. The current treatment options involve surgery, radiotherapy, targeted therapy, immunotherapy and the use of chemotherapeutic agents. Although the last approach is the most used, the high [...] Read more.
Melanoma is an aggressive form of skin cancer, being one of the deadliest cancers in the world. The current treatment options involve surgery, radiotherapy, targeted therapy, immunotherapy and the use of chemotherapeutic agents. Although the last approach is the most used, the high toxicity and the lack of efficacy in advanced stages of the disease have demanded the search for novel bioactive molecules and/or efficient drug delivery systems. The current review aims to discuss the most recent advances on the elucidation of potential targets for melanoma treatment, such as aquaporin-3 and tyrosinase. In addition, the role of nanotechnology as a valuable strategy to effectively deliver selective drugs is emphasized, either incorporating/encapsulating synthetic molecules or natural-derived compounds in lipid-based nanosystems such as liposomes. Nanoformulated compounds have been explored for their improved anticancer activity against melanoma and promising results have been obtained. Indeed, they displayed improved physicochemical properties and higher accumulation in tumoral tissues, which potentiated the efficacy of the compounds in pre-clinical experiments. Overall, these experiments opened new doors for the discovery and development of more effective drug formulations for melanoma treatment. Full article
(This article belongs to the Special Issue Multifunctional Nanocarriers for Drug Delivery)
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Open AccessArticle
Medium-Dependent Antibacterial Properties and Bacterial Filtration Ability of Reduced Graphene Oxide
Nanomaterials 2019, 9(10), 1454; https://doi.org/10.3390/nano9101454 - 13 Oct 2019
Viewed by 222
Abstract
Toxicity of reduced graphene oxide (rGO) has been a topic of multiple studies and was shown to depend on a variety of characteristics of rGO and biological objects of interest. In this paper, we demonstrate that when studying the same dispersions of rGO [...] Read more.
Toxicity of reduced graphene oxide (rGO) has been a topic of multiple studies and was shown to depend on a variety of characteristics of rGO and biological objects of interest. In this paper, we demonstrate that when studying the same dispersions of rGO and fluorescent Escherichia coli (E. coli) bacteria, the outcome of nanotoxicity experiments also depends on the type of culture medium. We show that rGO inhibits the growth of bacteria in a nutrition medium but shows little effect on the behavior of E. coli in a physiological saline solution. The observed effects of rGO on E. coli in different media could be at least partially rationalized through the adsorption of bacteria and nutrients on the dispersed rGO sheets, which is likely mediated via hydrogen bonding. We also found that the interaction between rGO and E. coli is medium-dependent, and in physiological saline solutions they form stable flocculate structures that were not observed in nutrition media. Furthermore, the aggregation of rGO and E. coli in saline media was observed regardless of whether the bacteria were alive or dead. Filtration of the aggregate suspensions led to nearly complete removal of bacteria from filtered liquids, which highlights the potential of rGO for the filtration and separation of biological contaminants, regardless of whether they include live or dead microorganisms. Full article
(This article belongs to the Special Issue Nanopharmaceutics)
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Open AccessArticle
Hydrothermal Fabrication of Spindle-Shaped ZnO/Palygorskite Nanocomposites Using Nonionic Surfactant for Enhancement of Antibacterial Activity
Nanomaterials 2019, 9(10), 1453; https://doi.org/10.3390/nano9101453 - 13 Oct 2019
Viewed by 154
Abstract
In order to improve the antibacterial performance of natural palygorskite, spindle-like ZnO/palygorskite (ZnO/PAL) nanocomposites with controllable growth of ZnO on the surface of PAL were prepared in the presence of non-ionic surfactants using an easy-to-operate hydrothermal method. The obtained ZnO/PAL nanocomposites have a [...] Read more.
In order to improve the antibacterial performance of natural palygorskite, spindle-like ZnO/palygorskite (ZnO/PAL) nanocomposites with controllable growth of ZnO on the surface of PAL were prepared in the presence of non-ionic surfactants using an easy-to-operate hydrothermal method. The obtained ZnO/PAL nanocomposites have a novel and special spindle-shaped structure and good antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and are also low cost. The minimum inhibitory concentrations of ZnO/PAL nanocomposites toward E. coli and S. aureus reached 1.5 and 5 mg/mL, respectively. Full article
(This article belongs to the Special Issue Nanoscale Surface Engineering)
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Open AccessArticle
Formation and Characterization of Hole Nanopattern on Photoresist Layer by Scanning Near-Field Optical Microscope
Nanomaterials 2019, 9(10), 1452; https://doi.org/10.3390/nano9101452 - 12 Oct 2019
Viewed by 83
Abstract
Patterning of lines of holes on a layer of positive photoresist SX AR-P 3500/6 (Allresist GmbH, Strausberg, Germany) spin-coated on a quartz substrate is carried out by using scanning near-field optical lithography. A green 532 nm-wavelength laser, focused on a backside of a [...] Read more.
Patterning of lines of holes on a layer of positive photoresist SX AR-P 3500/6 (Allresist GmbH, Strausberg, Germany) spin-coated on a quartz substrate is carried out by using scanning near-field optical lithography. A green 532 nm-wavelength laser, focused on a backside of a nanoprobe of 90 nm diameter, is used as a light source. As a result, after optimization of parameters like laser power, exposure time, or sleep time, it is confirmed that it is possible to obtain a uniform nanopattern structure in the photoresist layer. In addition, the lines of holes are characterized by a uniform depth (71–87 nm) and relatively high aspect ratio ranging from 0.22 to 0.26. Numerical modelling performed with a rigorous method shows that such a structure can be potentially used as a phase zone plate. Full article
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Open AccessArticle
3D-Printed Concentration-Controlled Microfluidic Chip with Diffusion Mixing Pattern for the Synthesis of Alginate Drug Delivery Microgels
Nanomaterials 2019, 9(10), 1451; https://doi.org/10.3390/nano9101451 - 12 Oct 2019
Viewed by 90
Abstract
Alginate as a good drug delivery vehicle has excellent biocompatibility and biodegradability. In the ionic gelation process between alginate and Ca2+, the violent reaction is the absence of a well-controlled strategy in the synthesizing calcium alginate (CaA) microgels. In this study, [...] Read more.
Alginate as a good drug delivery vehicle has excellent biocompatibility and biodegradability. In the ionic gelation process between alginate and Ca2+, the violent reaction is the absence of a well-controlled strategy in the synthesizing calcium alginate (CaA) microgels. In this study, a concentration-controlled microfluidic chip with central buffer flow was designed and 3D-printed to well-control the synthesis process of CaA microgels by the diffusion mixing pattern. The diffusion mixing pattern in the microfluidic chip can slow down the ionic gelation process in the central stream. The particle size can be influenced by channel length and flow rate ratio, which can be regulated to 448 nm in length and 235 nm in diameter. The delivery ratio of Doxorubicin (Dox) in CaA microgels are up to 90% based on the central stream strategy. [email protected] microgels with pH-dependent release property significantly enhances the cell killing rate against human breast cancer cells (MCF-7). The diffusion mixing pattern gives rise to well-controlled synthesis of CaA microgels, serving as a continuous and controllable production process for advanced drug delivery systems. Full article
(This article belongs to the Special Issue 3D Printing and Nanotechnology in Biology and Medical Applications)
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Open AccessArticle
Carbon Nanotube-Graphene Hybrid Electrodes with Enhanced Thermo-Electrochemical Cell Properties
Nanomaterials 2019, 9(10), 1450; https://doi.org/10.3390/nano9101450 - 12 Oct 2019
Viewed by 101
Abstract
Carbon nanotube-Graphene (CNT-Gr) hybrids were prepared on stainless steel substrates by the electrophoretic deposition (EPD) to make the thermo-electrochemical cell (TEC) electrodes. The as-obtained TEC electrodes were investigated by the SEM, XRD, Raman spectroscopy, tensile, and surface resistance tests. These hybrid electrodes exhibited [...] Read more.
Carbon nanotube-Graphene (CNT-Gr) hybrids were prepared on stainless steel substrates by the electrophoretic deposition (EPD) to make the thermo-electrochemical cell (TEC) electrodes. The as-obtained TEC electrodes were investigated by the SEM, XRD, Raman spectroscopy, tensile, and surface resistance tests. These hybrid electrodes exhibited significant improved TEC performances compared to the pristine CNT electrode. In addition, these hybrid electrodes could be optimized by tuning the contents of the graphene in the hybrids, and the CNT-Gr-0.1 hybrid electrode showed the best TEC performance with the current density of 62.8 A·m−2 and the power density of 1.15 W·m−2, 30.4% higher than the CNT electrode. The enhanced TEC performance is attributed to improvements in the electrical and thermal conductivities, as well as the adhesion between the CNT-Gr hybrid and the substrate. Meanwhile, the relative conversion efficiency of the TECs can reach 1.35%. The investigation suggests that the growth of CNT-Gr hybrid electrodes by the EPD technique may offer a promising approach for practical applications of the carbon nanomaterial-based TEC electrodes. Full article
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Open AccessReview
ZnO Nanostructures and Electrospun ZnO–Polymeric Hybrid Nanomaterials in Biomedical, Health, and Sustainability Applications
Nanomaterials 2019, 9(10), 1449; https://doi.org/10.3390/nano9101449 - 12 Oct 2019
Viewed by 132
Abstract
ZnO-based nanomaterials are a subject of increasing interest within current research, because of their multifunctional properties, such as piezoelectricity, semi-conductivity, ultraviolet absorption, optical transparency, and photoluminescence, as well as their low toxicity, biodegradability, low cost, and versatility in achieving diverse shapes. Among the [...] Read more.
ZnO-based nanomaterials are a subject of increasing interest within current research, because of their multifunctional properties, such as piezoelectricity, semi-conductivity, ultraviolet absorption, optical transparency, and photoluminescence, as well as their low toxicity, biodegradability, low cost, and versatility in achieving diverse shapes. Among the numerous fields of application, the use of nanostructured ZnO is increasingly widespread also in the biomedical and healthcare sectors, thanks to its antiseptic and antibacterial properties, role as a promoter in tissue regeneration, selectivity for specific cell lines, and drug delivery function, as well as its electrochemical and optical properties, which make it a good candidate for biomedical applications. Because of its growing use, understanding the toxicity of ZnO nanomaterials and their interaction with biological systems is crucial for manufacturing relevant engineering materials. In the last few years, ZnO nanostructures were also used to functionalize polymer matrices to produce hybrid composite materials with new properties. Among the numerous manufacturing methods, electrospinning is becoming a mainstream technique for the production of scaffolds and mats made of polymeric and metal-oxide nanofibers. In this review, we focus on toxicological aspects and recent developments in the use of ZnO-based nanomaterials for biomedical, healthcare, and sustainability applications, either alone or loaded inside polymeric matrices to make electrospun composite nanomaterials. Bibliographic data were compared and analyzed with the aim of giving homogeneity to the results and highlighting reference trends useful for obtaining a fresh perspective about the toxicity of ZnO nanostructures and their underlying mechanisms for the materials and engineering community. Full article
(This article belongs to the Special Issue The Two Faces of Nanomaterials: Toxicity and Bioactivity)
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Open AccessReview
Research Progress of M13 Bacteriophage-Based Biosensors
Nanomaterials 2019, 9(10), 1448; https://doi.org/10.3390/nano9101448 - 11 Oct 2019
Viewed by 155
Abstract
Recently, new virus-based sensor systems that operate on M13 bacteriophage infrastructure have attracted considerable attention. These systems can detect a range of chemicals with excellent sensitivity and selectivity. Filaments consistent with M13 bacteriophages can be ordered by highly established forms of self-assembly. This [...] Read more.
Recently, new virus-based sensor systems that operate on M13 bacteriophage infrastructure have attracted considerable attention. These systems can detect a range of chemicals with excellent sensitivity and selectivity. Filaments consistent with M13 bacteriophages can be ordered by highly established forms of self-assembly. This allows M13 bacteriophages to build a homogeneous distribution and infiltrate the network structure of nanostructures under mild conditions. Phage display, involving the genetic engineering of M13 bacteriophages, is another strong feature of the M13 bacteriophage as a functional building block. The numerous genetic modification possibilities of M13 bacteriophages are clearly the key features, and far more applications are envisaged. This paper reviews the recent progress in the application of the M13 bacteriophage self-assembly structures through to sensor systems and discusses future M13 bacteriophage technology. Full article
(This article belongs to the Special Issue Virus-Based Nanomaterials and Nanostructures)
Open AccessArticle
Influence of Semiconductor Morphology on Photocatalytic Activity of Plasmonic Photocatalysts: Titanate Nanowires and Octahedral Anatase Nanoparticles
Nanomaterials 2019, 9(10), 1447; https://doi.org/10.3390/nano9101447 - 11 Oct 2019
Viewed by 140
Abstract
Octahedral anatase particles (OAP) with eight exposed and thermodynamically most stable (101) facets were prepared by an ultrasonication-hydrothermal (US-HT) reaction from potassium titanate nanowires (TNW). The precursor (TNW) and the product (OAP) of US-HT reaction were modified with nanoparticles of noble metals (Au, [...] Read more.
Octahedral anatase particles (OAP) with eight exposed and thermodynamically most stable (101) facets were prepared by an ultrasonication-hydrothermal (US-HT) reaction from potassium titanate nanowires (TNW). The precursor (TNW) and the product (OAP) of US-HT reaction were modified with nanoparticles of noble metals (Au, Ag or Pt) by photodeposition. Samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), scanning transmission electron microscopy (STEM) and time-resolved microwave conductivity (TRMC). The photocatalytic activity was investigated in three reaction systems, i.e., anaerobic dehydrogenation of methanol and oxidative decomposition of acetic acid under UV/vis irradiation, and oxidation of 2-propanol under vis irradiation. It was found that hydrogen liberation correlated with work function of metals, and thus the most active were platinum-modified samples. Photocatalytic activities of bare and modified OAP samples were much higher than those of TNW samples, probably due to anatase presence, higher crystallinity and electron mobility in faceted NPs. Interestingly, noble metals showed different influence on the activity depending on the semiconductor support, i.e., gold-modified TNW and platinum-modified OAP exhibited the highest activity for acetic acid decomposition, whereas silver- and gold-modified samples were the most active under vis irradiation, respectively. It is proposed that the form of noble metal (metallic vs. oxidized) as well as the morphology (well-organized vs. uncontrolled) have a critical effect on the overall photocatalytic performance. TRMC analysis confirmed that fast electron transfer to noble metal is a key factor for UV activity. It is proposed that the efficiency of plasmonic photocatalysis (under vis irradiation) depends on the oxidation form of metal (zero-valent preferable), photoabsorption properties (broad localized surface plasmon resonance (LSPR)), kind of metal (silver) and counteraction of “hot” electrons back transfer to noble metal NPs (by controlled morphology and high crystallinity). Full article
(This article belongs to the Special Issue Nano‐Photocatalytic Materials: Possibilities and Challenges)
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Open AccessArticle
Template-Assisted Co-Ni Nanowire Arrays
Nanomaterials 2019, 9(10), 1446; https://doi.org/10.3390/nano9101446 - 11 Oct 2019
Viewed by 132
Abstract
A comparison was performed between Co-Ni thin films and template-assisted nanowires arrays obtained by electrochemical co-deposition. To reduce the effects of anomalous deposition and increase the Ni content in the deposit, an electrolyte with three times more Ni than Co in atomic ratio [...] Read more.
A comparison was performed between Co-Ni thin films and template-assisted nanowires arrays obtained by electrochemical co-deposition. To reduce the effects of anomalous deposition and increase the Ni content in the deposit, an electrolyte with three times more Ni than Co in atomic ratio was chosen. Electrochemical deposition was performed at constant potentials chosen in the range from E = −0.8 to −1.2 V vs. Ag/AgCl. Cyclic voltammetry, chronoamperometry, and charge stripping techniques were used to characterize and compare the electrochemical behavior of Co-Ni films and nanowires. Morphological and compositional characterization was performed by scanning electron microscopy (SEM/EDAX) to assess the influence of the deposition potential on the growth of film and nanowires. A comprehensive analysis of the deposit growth rates for thin films and nanowires is presented taking into consideration the hydrogen evolution and anomalous deposition. The comparative study of the composition of film and nanowires obtained at different deposition potentials has shown that deposition of nanowires with a film-like composition takes place at more positive potential than thin film. Full article
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Open AccessArticle
Reductive and Coordinative Effects of Hydrazine in Structural Transformations of Copper Hydroxide Nanoparticles
Nanomaterials 2019, 9(10), 1445; https://doi.org/10.3390/nano9101445 - 11 Oct 2019
Viewed by 96
Abstract
Shape-specific copper oxide nanostructures have attracted increasing attention due to their widespread applications in energy conversion, sensing, and catalysis. Advancing our understanding of structure, composition, and surface chemistry transformations in shaped copper oxide nanomaterials during changes in copper oxidation state is instrumental from [...] Read more.
Shape-specific copper oxide nanostructures have attracted increasing attention due to their widespread applications in energy conversion, sensing, and catalysis. Advancing our understanding of structure, composition, and surface chemistry transformations in shaped copper oxide nanomaterials during changes in copper oxidation state is instrumental from both applications and preparative nanochemistry standpoints. Here, we report the study of structural and compositional evolution of amorphous copper (II) hydroxide nanoparticles under hydrazine reduction conditions that resulted in the formation of crystalline Cu2O and composite Cu2O-N2H4 branched particles. The structure of the latter was influenced by the solvent medium. We showed that hydrazine, while being a common reducing agent in nanochemistry, can not only reduce the metal ions but also coordinate to them as a bidentate ligand and thereby integrate within the lattice of a particle. In addition to shape and composition transformation of individual particles, concurrent interparticle attachment and ensemble shape evolution were induced by depleting surface stabilization of individual nanoparticles. Not only does this study provide a facile synthetic method for several copper (I) oxide structures, it also demonstrates the complex behavior of a reducing agent with multidentate coordinating ability in nanoparticle synthesis. Full article
(This article belongs to the Special Issue Novel Nanomaterials for Applications in Energy and Catalysis)
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Open AccessReview
TiO2-based Photocatalytic Cementitious Composites: Materials, Properties, Influential Parameters, and Assessment Techniques
Nanomaterials 2019, 9(10), 1444; https://doi.org/10.3390/nano9101444 - 11 Oct 2019
Viewed by 92
Abstract
Applications of heterogeneous photocatalytic processes based on semiconductor particles in cement-based materials have received great attention in recent years in enhancing the aesthetic durability of buildings and reducing global environmental pollution. Amongst all, titanium dioxide (TiO2) is the most widely used [...] Read more.
Applications of heterogeneous photocatalytic processes based on semiconductor particles in cement-based materials have received great attention in recent years in enhancing the aesthetic durability of buildings and reducing global environmental pollution. Amongst all, titanium dioxide (TiO2) is the most widely used semiconductor particle in structural materials with photocatalytic activity because of its low cost, chemically stable nature, and absence of toxicity. Utilization of TiO2 in combination with cement-based materials would plunge the concentration of urban pollutants such as NOx. In fact, cementitious composites containing TiO2 have already found applications in self-cleaning buildings, antimicrobial surfaces, and air-purifying structures. This paper aims to present a comprehensive review on TiO2-based photocatalysis cement technology, its practical applications, and research gaps for further progression of cementitious materials with photocatalytic activity. Full article
(This article belongs to the Special Issue Photocatalytic Nanomaterials)
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Open AccessArticle
Reusable Surface-Modified Bacterial Cellulose Based on Atom Transfer Radical Polymerization Technology with Excellent Catalytic Properties
Nanomaterials 2019, 9(10), 1443; https://doi.org/10.3390/nano9101443 - 11 Oct 2019
Viewed by 81
Abstract
The high catalytic activity of membrane-binding gold nanoparticles (AuNPs) makes its application in oxidation or reduction an attractive challenge. Herein, surface-functionalized bacterial cellulose (BC-poly(HEMA)) was successfully prepared with 2-hydroxyethyl methacrylate (HEMA) as monomers via the atom transfer radical polymerization (ATRP) method. BC-poly(HEMA) was [...] Read more.
The high catalytic activity of membrane-binding gold nanoparticles (AuNPs) makes its application in oxidation or reduction an attractive challenge. Herein, surface-functionalized bacterial cellulose (BC-poly(HEMA)) was successfully prepared with 2-hydroxyethyl methacrylate (HEMA) as monomers via the atom transfer radical polymerization (ATRP) method. BC-poly(HEMA) was further utilized as not only reducing agent but also carrier for uniform distribution of the AuNPs in the diameter of about 8 nm on the membrane surface during the synthesis stage. The synthesized AuNPs/BC-poly(HEMA) exhibited excellent catalytic activity and reusability for reducing 4-nitrophenol (4-NP) from NaBH4. The results proved that the catalytic performance of AuNPs/BC-poly(HEMA) was affected by the surrounding temperature and pH, and AuNPs/BC-poly(HEMA) maintained the extremely high catalytic activity of AuNPs/BC-poly(HEMA) even after 10 reuses. In addition, no 4-NP was detected in the degradation solution after being stored for 45 days. The reusable catalyst prepared by this work shows a potential industrial application prospect. Full article
(This article belongs to the Special Issue Nanocatalysts in Chemistry: Synthesis and Applications)
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Open AccessEditorial
Solution Synthesis, Processing, and Applications of Semiconducting Nanomaterials
Nanomaterials 2019, 9(10), 1442; https://doi.org/10.3390/nano9101442 - 11 Oct 2019
Viewed by 87
Abstract
Nanomaterials have contributed to the forefront of materials research in the past two decades, and are used today in sensors, solar cells, light emitting diodes, electronics, and biomedical devices [...] Full article
Open AccessArticle
Effect of GO Additive in ZnO/rGO Nanocomposites with Enhanced Photosensitivity and Photocatalytic Activity
Nanomaterials 2019, 9(10), 1441; https://doi.org/10.3390/nano9101441 - 11 Oct 2019
Viewed by 102
Abstract
Zinc oxide/reduced graphene oxide nanocomposites (ZnO/rGO) are synthesized via a simple one-pot solvothermal technique. The nanoparticle–nanorod turnability was achieved with the increase in GO additive, which was necessary to control the defect formation. The optimal defect in ZnO/rGO not only increased ZnO/rGO surface [...] Read more.
Zinc oxide/reduced graphene oxide nanocomposites (ZnO/rGO) are synthesized via a simple one-pot solvothermal technique. The nanoparticle–nanorod turnability was achieved with the increase in GO additive, which was necessary to control the defect formation. The optimal defect in ZnO/rGO not only increased ZnO/rGO surface and carrier concentration, but also provided the alternative carrier pathway assisted with rGO sheet for electron–hole separation and prolonging carrier recombination. These properties are ideal for photodetection and photocatalytic applications. For photosensing properties, ZnO/rGO shows the improvement of photosensitivity compared with pristine ZnO from 1.51 (ZnO) to 3.94 (ZnO/rGO (20%)). Additionally, applying bending strain on ZnO/rGO enhances its photosensitivity even further, as high as 124% at r = 12.5 mm, due to improved surface area and induced negative piezoelectric charge from piezoelectric effect. Moreover, the photocatalytic activity with methylene blue (MB) was studied. It was observed that the rate of MB degradation was higher in presence of ZnO/rGO than pristine ZnO. Therefore, ZnO/rGO became a promising materials for different applications. Full article
(This article belongs to the Special Issue Multifunctional Graphene-Based Nanocomposites)
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Open AccessArticle
Bacterial Compatibility/Toxicity of Biogenic Silica (b-SiO2) Nanoparticles Synthesized from Biomass Rice Husk Ash
Nanomaterials 2019, 9(10), 1440; https://doi.org/10.3390/nano9101440 - 11 Oct 2019
Viewed by 129
Abstract
Biogenic silica (b-SiO2) nanopowders from rice husk ash (RHA) were prepared by chemical method and their bacterial compatibility/toxicity was analyzed. The X-ray diffractometry (XRD) patterns of the b-SiO2 nanopowders indicated an amorphous feature due to the absence of any sharp [...] Read more.
Biogenic silica (b-SiO2) nanopowders from rice husk ash (RHA) were prepared by chemical method and their bacterial compatibility/toxicity was analyzed. The X-ray diffractometry (XRD) patterns of the b-SiO2 nanopowders indicated an amorphous feature due to the absence of any sharp peaks. Micrographs of the b-SiO2 revealed that sticky RHA synthesized SiO2 nanopowder (S1) had clustered spherical nanoparticles (70 nm diameter), while b-SiO2 nanopowder synthesized from red RHA (S2) and b-SiO2 nanopowder synthesized from brown RHA (S3) were purely spherical (20 nm and 10 nm diameter, respectively). Compared to the S1 (11.36 m2g−1) and S2 (234.93 m2g−1) nanopowders, the S3 nanopowders showed the highest surface area (280.16 m2g−1) due to the small particle size and high porosity. The core level of the X-ray photoelectron spectroscopy (XPS) spectra showed that Si was constituted by two components, Si 2p (102.2 eV) and Si 2s (153.8 eV), while Oxygen 1s was observed at 531.8 eV, confirming the formation of SiO2. The anti-bacterial activity of the b-SiO2 nanopowders was investigated using both gram-positive (Escherichia coli) and gram-negative (Staphylococcus aureus) microorganisms. Compared to S2 and S3 silica nanopowders, S1 demonstrated enhanced antibacterial activity. This study signifies the medical, biomedical, clinical, and biological importance and application of RHA-mediated synthesized b-SiO2. Full article
(This article belongs to the Special Issue Antibacterial Activity of Nanoparticles)
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Open AccessArticle
Spectral Modulation of Optofluidic Coupled-Microdisk Lasers in Aqueous Media
Nanomaterials 2019, 9(10), 1439; https://doi.org/10.3390/nano9101439 - 11 Oct 2019
Viewed by 119
Abstract
We present the spectral modulation of an optofluidic microdisk device and investigate the mechanism and characteristics of the microdisk laser in aqueous media. The optofluidic microdisk device combines a solid-state dye-doped polymer microdisk with a microfluidic channel device, whose optical field can interact [...] Read more.
We present the spectral modulation of an optofluidic microdisk device and investigate the mechanism and characteristics of the microdisk laser in aqueous media. The optofluidic microdisk device combines a solid-state dye-doped polymer microdisk with a microfluidic channel device, whose optical field can interact with the aqueous media. Interesting phenomena, such as mode splitting and single-mode lasing in the laser spectrum, can be observed in two coupled microdisks under the pump laser. We modulated the spectra by changing the gap of the two coupled microdisks, the refractive indices of the aqueous media, and the position of a pump light, namely, selective pumping schemes. This optofluidic microlaser provides a method to modulate the laser spectra precisely and flexibly, which will help to further understand spectral properties of coupled microcavity laser systems and develop potential applications in photobiology and photomedicine. Full article
(This article belongs to the Special Issue Dynamics and Applications of Photon-Nanostructured Systems)
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Open AccessArticle
Elongated Flexuous Plant Virus-Derived Nanoparticles Functionalized for Autoantibody Detection
Nanomaterials 2019, 9(10), 1438; https://doi.org/10.3390/nano9101438 - 10 Oct 2019
Viewed by 173
Abstract
Nanoparticles derived from the elongated flexuous capsids of Turnip mosaic virus (TuMV) have been shown to be efficient tools for antibody sensing with a very high sensitivity if adequately functionalized with the corresponding epitopes. Taking advantage of this possibility, TuMV virus-like particles (VLPs) [...] Read more.
Nanoparticles derived from the elongated flexuous capsids of Turnip mosaic virus (TuMV) have been shown to be efficient tools for antibody sensing with a very high sensitivity if adequately functionalized with the corresponding epitopes. Taking advantage of this possibility, TuMV virus-like particles (VLPs) have been genetically derivatized with a peptide from the chaperonin Hsp60, a protein described to be involved in inflammation processes and autoimmune diseases. Antibodies against the peptide have been previously shown to have a diagnostic value in at least one autoimmune disease, multiple sclerosis. The functionalized Hsp60-VLPs showed their significant increase in sensing potency when compared to monoclonal antibody detection of the peptide in a conventional immunoassay. Additionally, the developed Hsp60-VLPs allowed the detection of autoantibodies against the Hsp60 peptide in an in vivo mouse model of dextran sodium sulfate (DSS)-induced colitis. The detection of minute amounts of the autoantibodies allowed us to perform the analysis of their evolution during the progression of the disease. The anti-Hsp60 autoantibody levels in the sera of the inflamed mice went down during the induction phase of the disease. Increased levels of the anti-HSP60 autoantibodies were detected during the resolution phase of the disease. An extension of a previously proposed model for the involvement of Hsp60 in inflammatory processes is considered, incorporating a role for Hsp60 autoantibodies. This, and related models, can now be experimentally tested thanks to the autoantibody detection hypersensitivity provided by the functionalized VLPs. Full article
(This article belongs to the Special Issue Virus-Based Nanomaterials and Nanostructures)
Open AccessArticle
Preparation of Pd/C by Atmospheric-Pressure Ethanol Cold Plasma and Its Preparation Mechanism
Nanomaterials 2019, 9(10), 1437; https://doi.org/10.3390/nano9101437 - 10 Oct 2019
Viewed by 109
Abstract
Treatment with atmospheric-pressure (AP) hydrogen cold plasma is an effective method for preparing highly active supported metal catalytic materials. However, this technique typically uses H2 as working gas, which is explosive and difficult to transport. This study proposes the use of PdCl [...] Read more.
Treatment with atmospheric-pressure (AP) hydrogen cold plasma is an effective method for preparing highly active supported metal catalytic materials. However, this technique typically uses H2 as working gas, which is explosive and difficult to transport. This study proposes the use of PdCl2 as a Pd precursor and activated carbon as the support to fabricate Pd/C catalytic materials (Pd/C-EP-Ar) by using ethanol—which is renewable, easily stored, and safe—combined with AP cold plasma (AP ethanol cold plasma) followed by calcination in Ar gas at 550 °C for 2 h. Both Pd/C-EP and Pd/C-HP fabricated using AP ethanol and hydrogen cold plasma (without calcination in Ar gas) respectively, exhibit low CO oxidation reactivity. The activity of Pd/C-EP is lower than Pd/C-HP, which is mainly ascribed to the carbon layer formed by ethanol decomposition during plasma treatment. However, the 100% CO conversion temperature (T100) of Pd/C-EP-Ar is 140 °C, which is similar to that of Pd/C-HP-Ar fabricated using AP hydrogen cold plasma (calcined in Ar gas at 550 °C for 2 h). The characterization results of X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy indicated that the carbon layer formed by ethanol decomposition enhanced the interaction of metal nanoparticles to the support, and a high Pd/C atomic ratio was obtained. This was beneficial to the high CO oxidation performance. This work provides a safe method for synthesizing high-performance Pd/C catalytic materials avoiding the use of H2, which is explosive and difficult to transport. Full article
(This article belongs to the Special Issue Nanocatalysts in Chemistry: Synthesis and Applications)
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Open AccessReview
A Review on the Promising Plasma-Assisted Preparation of Electrocatalysts
Nanomaterials 2019, 9(10), 1436; https://doi.org/10.3390/nano9101436 - 10 Oct 2019
Viewed by 111
Abstract
Electrocatalysts are becoming increasingly important for both energy conversion and environmental catalysis. Plasma technology can realize surface etching and heteroatom doping, and generate highly dispersed components and redox species to increase the exposure of the active edge sites so as to improve the [...] Read more.
Electrocatalysts are becoming increasingly important for both energy conversion and environmental catalysis. Plasma technology can realize surface etching and heteroatom doping, and generate highly dispersed components and redox species to increase the exposure of the active edge sites so as to improve the surface utilization and catalytic activity. This review summarizes the recent plasma-assisted preparation methods of noble metal catalysts, non-noble metal catalysts, non-metal catalysts, and other electrochemical catalysts, with emphasis on the characteristics of plasma-assisted methods. The influence of the morphology, structure, defect, dopant, and other factors on the catalytic performance of electrocatalysts is discussed. Full article
(This article belongs to the Special Issue Plasma for Energy and Catalytic Nanomaterials)
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Open AccessReview
Biomimetic Hydroxyapatite on Graphene Supports for Biomedical Applications: A Review
Nanomaterials 2019, 9(10), 1435; https://doi.org/10.3390/nano9101435 - 10 Oct 2019
Viewed by 113
Abstract
Hydroxyapatite (HA) has been widely used in fields of materials science, tissue engineering, biomedicine, energy and environmental science, and analytical science due to its simple preparation, low-cost, and high biocompatibility. To overcome the weak mechanical properties of pure HA, various reinforcing materials were [...] Read more.
Hydroxyapatite (HA) has been widely used in fields of materials science, tissue engineering, biomedicine, energy and environmental science, and analytical science due to its simple preparation, low-cost, and high biocompatibility. To overcome the weak mechanical properties of pure HA, various reinforcing materials were incorporated with HA to form high-performance composite materials. Due to the unique structural, biological, electrical, mechanical, thermal, and optical properties, graphene has exhibited great potentials for supporting the biomimetic synthesis of HA. In this review, we present recent advance in the biomimetic synthesis of HA on graphene supports for biomedical applications. More focuses on the biomimetic synthesis methods of HA and HA on graphene supports, as well as the biomedical applications of biomimetic graphene-HA nanohybrids in drug delivery, cell growth, bone regeneration, biosensors, and antibacterial test are performed. We believe that this review is state-of-the-art, and it will be valuable for readers to understand the biomimetic synthesis mechanisms of HA and other bioactive minerals, at the same time it can inspire the design and synthesis of graphene-based novel nanomaterials for advanced applications. Full article
(This article belongs to the Special Issue Multifunctional Graphene-Based Nanocomposites)
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Open AccessArticle
A Facile Method to Prepare Silver Doped Graphene Combined with Polyaniline for High Performances of Filter Paper Based Flexible Electrode
Nanomaterials 2019, 9(10), 1434; https://doi.org/10.3390/nano9101434 - 10 Oct 2019
Viewed by 97
Abstract
A flexible filter paper based composite electrode was prepared via the convenient one-step synthesis of silver doped graphene for the first time, followed by in-situ polymerization of aniline monomers. Using L-ascorbic acid for simultaneous reduction of grapheme oxide and silver nitrate, we provided [...] Read more.
A flexible filter paper based composite electrode was prepared via the convenient one-step synthesis of silver doped graphene for the first time, followed by in-situ polymerization of aniline monomers. Using L-ascorbic acid for simultaneous reduction of grapheme oxide and silver nitrate, we provided a new and green method to prepare graphene hybrid sheets without toxicity. It was found that the as-fabricated hybrid electrode formed a three-dimensional porous architecture, which not only increased the specific surface area of composite, but also facilitated the ion diffusion of the electrolyte. In addition, according to the tests of electrochemical performances, the flexible hybrid electrode subsequently exhibited exceptional specific capacitance of 437.3 F/g, energy density of 1133.5 W·h/kg and power density of 88.8 kW/kg, respectively. Meanwhile, the as-prepared hybrid demonstrated a good cycling stability with only 10.99% specific capacitance deterioration after 5000 times of cycling. This preparation technology presented here shows great potential for the development and application of wearable and portable energy storage devices, particularly for flexible supercapacitors. Moreover, this study puts forward a general, simple and low-cost route of fabricating a novel flexible electrode on a large scale, eventually for environmental protection. Full article
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Open AccessArticle
Ultra-High Refractive Index Sensing Structure Based on a Metal-Insulator-Metal Waveguide-Coupled T-Shape Cavity with Metal Nanorod Defects
Nanomaterials 2019, 9(10), 1433; https://doi.org/10.3390/nano9101433 - 10 Oct 2019
Viewed by 131
Abstract
An ultra-high plasmonic refractive index sensing structure composed of a metal–insulator–metal (MIM) waveguide coupled to a T-shape cavity and several metal nanorod defects is proposed and investigated by using finite element method. The designed plasmonic MIM waveguide can constitute a cavity resonance zone [...] Read more.
An ultra-high plasmonic refractive index sensing structure composed of a metal–insulator–metal (MIM) waveguide coupled to a T-shape cavity and several metal nanorod defects is proposed and investigated by using finite element method. The designed plasmonic MIM waveguide can constitute a cavity resonance zone and the metal nanorod defects can effectively trap the light in the T-shape cavity. The results reveal that both the size of defects in wider rectangular cavity and the length of narrower rectangular cavity are primary factors increasing the sensitivity performance. The sensitivity can achieve as high as 8280 nm/RIU (RIU denotes the refractive index unit), which is the highest sensitivity reported in plasmonic MIM waveguide-based sensors to our knowledge. In addition, the proposed structure can also serve as a temperature sensor with temperature sensitivity as high as 3.30 nm/°C. The designed structure with simplicity and ease of fabrication can be applied in sensitivity nanometer scale refractive index sensor and may potentially be used in optical on-chip nanosensor. Full article
(This article belongs to the Special Issue Nanobiophotonics, Photomedicine, and Imaging)
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Open AccessCommunication
A Facile Method for Preparing UiO-66 Encapsulated Ru Catalyst and its Application in Plasma-Assisted CO2 Methanation
Nanomaterials 2019, 9(10), 1432; https://doi.org/10.3390/nano9101432 - 10 Oct 2019
Viewed by 91
Abstract
With increasing applications of metal-organic frameworks (MOFs) in the field of gas separation and catalysis, the preparation and performance research of encapsulating metal nanoparticles (NPs) into MOFs ([email protected]) have attracted extensive attention recently. Herein, an [email protected] catalyst is prepared by a one-step method. [...] Read more.
With increasing applications of metal-organic frameworks (MOFs) in the field of gas separation and catalysis, the preparation and performance research of encapsulating metal nanoparticles (NPs) into MOFs ([email protected]) have attracted extensive attention recently. Herein, an [email protected] catalyst is prepared by a one-step method. Ru NPs are encapsulated in situ in the UiO-66 skeleton structure during the synthesis of UiO-66 metal-organic framework via a solvothermal method, and its catalytic activity for CO2 methanation with the synergy of cold plasma is studied. The crystallinity and structural integrity of UiO-66 is maintained after encapsulating Ru NPs according to the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). As illustrated by X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM), and mapping analysis, the Ru species of the hydration ruthenium trichloride precursor are reduced to metallic Ru NPs without additional reducing processes during the synthesis of [email protected], and the Ru NPs are uniformly distributed inside the [email protected] Thermogravimetric analysis (TGA) and N2 sorption analysis show that the specific surface area and thermal stability of [email protected] decrease slightly compared with that of UiO-66 and was ascribed to the encapsulation of Ru NPs in the UiO-66 skeleton. The results of plasma-assisted catalytic CO2 methanation indicate that [email protected] exhibits excellent catalytic activity. CO2 conversion and CH4 selectivity over [email protected] reached 72.2% and 95.4% under 13.0 W of discharge power and a 30 mL·min−1 gas flow rate ( V H 2 : V C O 2 = 4 : 1 ), respectively. Both values are significantly higher than pure UiO-66 with plasma and Ru/Al2O3 with plasma. The enhanced performance of [email protected] is attributed to its unique framework structure and excellent dispersion of Ru NPs. Full article
(This article belongs to the Special Issue Novel Nanomaterials for Applications in Energy and Catalysis)
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Open AccessArticle
The Synergistic Effect of Zinc Ferrite Nanoparticles Uniformly Deposited on Silver Nanowires for the Biofilm Inhibition of Candida albicans
Nanomaterials 2019, 9(10), 1431; https://doi.org/10.3390/nano9101431 - 10 Oct 2019
Viewed by 120
Abstract
Near-monodisperse zinc ferrite nanoparticles (ZnFe2O4 NPs) are synthesized by a co-precipitation method and deposited on the surface of silver nanowires (AgNWs), employing a stepwise solution method. The resulting hybrid nanostructures (ZnFe2O4@AgNWs) show a thin and uniform [...] Read more.
Near-monodisperse zinc ferrite nanoparticles (ZnFe2O4 NPs) are synthesized by a co-precipitation method and deposited on the surface of silver nanowires (AgNWs), employing a stepwise solution method. The resulting hybrid nanostructures (ZnFe2O4@AgNWs) show a thin and uniform layer of ZnFe2O4 NPs at an optimum weight ratio of 1:6 between the two component nanostructures. The hybrid nanostructures retain the high crystal quality and phase purity of their constituents. It is demonstrated that the ZnFe2O4@AgNWs hybrid nanostructures are effective at inhibiting the biofilm formation of Candida albicans cells. The biofilm inhibition activity of the hybrid nanostructures is estimated to be more than 50% at a low concentration of 100 µg/mL from both crystal violet assay and XTT assay, which are more than 8-fold higher than those of pure AgNWs and ZnFe2O4 NPs. This greatly enhanced biofilm inhibition activity is attributed to the ZnFe2O4 NPs-carrying membrane penetration by AgNWs and the subsequent interaction between Candida cells and ZnFe2O4 NPs. These results indicate that the ZnFe2O4@AgNWs hybrid nanostructures have great potential as a new type of novel antibiofilm agent. Full article
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Open AccessArticle
Potential Application of Graphene/Antimonene Herterostructure as an Anode for Li-Ion Batteries: A First-Principles Study
Nanomaterials 2019, 9(10), 1430; https://doi.org/10.3390/nano9101430 - 10 Oct 2019
Viewed by 116
Abstract
To suppress the volume expansion and thus improve the performance of antimonene as a promising anode for lithium-ion batteries, we have systematically studied the stability, structural and electronic properties of the antimonene capped with graphene (G/Sb heterostructure) upon the intercalation and diffusion of [...] Read more.
To suppress the volume expansion and thus improve the performance of antimonene as a promising anode for lithium-ion batteries, we have systematically studied the stability, structural and electronic properties of the antimonene capped with graphene (G/Sb heterostructure) upon the intercalation and diffusion of Li atoms by first-principles calculations based on van der Waals (vdW) corrected density functional theory. G/Sb exhibits higher Young’s modulus (armchair: 145.20, zigzag: 144.36 N m−1) and improved electrical conductivity (bandgap of 0.03 eV) compared with those of antimonene. Li favors incorporating into the interlayer region of G/Sb rather than the outside surfaces of graphene and antimonene of G/Sb heterostructure, which is caused by the synergistic effect. The in-plane lattice constants of G/Sb heterostructure expand only around 4.5%, and the interlayer distance of G/Sb increases slightly (0.22 Å) at the case of fully lithiation, which indicates that the capping of graphene on antimonene can effectively suppress the volumetric expansion during the charging process. Additionally, the hybrid G/Sb heterostructure has little influence on the migration behaviors of Li on the outside of graphene and Sb surfaces compared with their free-standing monolayers. However, the migration energy barrier for Li diffusion in the interlayer region (about 0.59 eV) is significantly affected by the geometry structure, which can be reduced to 0.34 eV simply by increasing the interlayer distance. The higher theoretical specific capacity (369.03 mAh g−1 vs 208 mAh g−1 for antimonene monolayer) and suitable open circuit voltage (from 0.11 V to 0.89 V) of G/Sb heterostructure are beneficial for anode materials of lithium-ion batteries. The above results reveal that G/Sb heterostructure may be an ideal candidate of anode for high recycling–rate and portable lithium-ion batteries. Full article
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Open AccessArticle
New Insights into the Interaction between Graphene Oxide and Beta-Blockers
Nanomaterials 2019, 9(10), 1429; https://doi.org/10.3390/nano9101429 - 09 Oct 2019
Viewed by 127
Abstract
As a nano-adsorbent, magnetic graphene oxide (GO/Fe3O4) was synthesized to potentially adsorb propranolol (PRO) from water. The synthetic material was characterized by SEM, TEM, VSM, FTIR, XRD, zeta potential, and XPS. The environmental factors, such as pH, humic acid [...] Read more.
As a nano-adsorbent, magnetic graphene oxide (GO/Fe3O4) was synthesized to potentially adsorb propranolol (PRO) from water. The synthetic material was characterized by SEM, TEM, VSM, FTIR, XRD, zeta potential, and XPS. The environmental factors, such as pH, humic acid concentration, PRO concentration, and contact time, were investigated regarding their effect on the adsorption process. The kinetics data fitted the pseudo first-order and second-order kinetics equations. The Langmuir equation, the Freundlich equation, and the Sips equation were used to analyze the adsorption isotherms. Electrostatic attraction, hydrogen bonding, and the π–π interaction all contributed to the adsorption process of PRO onto GO/Fe3O4. The discovery of this study emphasized the feasibility of GO/Fe3O4 removal of PRO and expanded the scope of the application of GO. Full article
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