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This review article presents the biomimetic helical inclusion of amylose toward hydrophobic polyesters as guests through a vine-twining polymerization process, which has been performed in the glucan phosphorylase (GP)-catalyzed enzymatic polymerization field to fabricate supramolecules and other nanostructured materials. Amylose, which is a representative abundant glucose polymer (polysaccharide) with left-handed helical conformation, is well known to include a number of hydrophobic guest molecules with suitable geometry and size in its cavity to construct helical inclusion complexes. Pure amylose is prepared through enzymatic polymerization of α-d-glucose 1-phosphate as a monomer using a maltooligosaccharide as a primer, catalyzed by GP. It is reported that the elongated amylosic chain at the nonreducing end in enzymatic polymerization twines around guest polymers with suitable structures and moderate hydrophobicity, which is dispersed in aqueous polymerization media, to form amylosic nanostructured inclusion complexes. As the image of this system is similar to how vines of a plant grow around a support rod, this polymerization has been named 'vine-twining polymerization'. In particular, the helical inclusion behavior of the enzymatically produced amylose toward hydrophobic polyesters depending on their structures, e.g., chain lengths and substituents, has been systematically investigated in the vine-twining polymerization field. Furthermore, amylosic supramolecular network materials, such as hydrogels, are fabricated through vine-twining polymerization by using copolymers, where hydrophobic polyester guests or maltooligosaccharide primers are covalently modified on hydrophilic main-chain polymers. The vine-twining polymerization using such copolymers in the appropriate systems induces the formation of amylosic nanostructured inclusion complexes among them, which act as cross-linking points, giving rise to supramolecular networks at the nanoscale. The resulting materials form supramolecular hydrogels, films, and microparticles. [ABSTRACT FROM AUTHOR]

Flexible and effective methods for oil–water separation are crucial for reducing pollutant emissions and safeguarding water and fuel resources. In recent years, there has been growing interest in fundamental research and engineering applications related to water and fuel purification, especially oil–water separation. To date, filter materials with special wetting characteristics have been widely used in oil–water separation. Nanostructured materials are one of the most attractive candidates for next-generation oil–water separation. This review systematically summarizes the mechanisms and current status of oil–water separation using nanostructured materials. Basically, this can be achieved by using nanostructured materials with specific wettability and nanostructures. Here, we provide a detailed discussion of two general approaches and their filtration mechanisms: (1) the selective filtration technique, based on specific surface wettability, which allows only oil or water to penetrate while blocking impurities; (2) the absorption technique, employing porous sponges, fibers, or aerogels, which selectively absorbs impure oil or water droplets. Furthermore, the main failure modes are discussed in this review. The purposes of this article are: (1) to summarize the methods of oil–water separation by nanotechnology; (2) to raise the level of environmental protection consciousness of water pollution by using nanotechnology; (3) to tease out the features of different approaches and provide a pivotal theoretical basis to optimize the performance of filtering materials. Several approaches for oil and water separation are compared. Furthermore, the principle and application scope of each method are introduced. [ABSTRACT FROM AUTHOR]

Polymers are the backbone of drug delivery. Electrospinning has greatly enriched the strategies that have been explored for developing novel drug delivery systems using polymers during the past two decades. In this study, four different kinds of polymers, i.e., the water-soluble polymer poly (vinyl alcohol) (PVA), the insoluble polymer poly(ε-caprolactone) (PCL), the insoluble polymer Eudragit RL100 (ERL100) and the pH-sensitive polymer Eudragit S100 (ES100) were successfully converted into types of tri-layer tri-polymer core–shell fibers through bi-fluid coaxial electrospinning. During the coaxial process, the model drug metronidazole (MTD) was loaded into the shell working fluid, which was an emulsion. The micro-formation mechanism of the tri-layer core–shell fibers from the coaxial emulsion electrospinning was proposed. Scanning electron microscope and transmission electron microscope evaluations verified the linear morphology of the resultant fibers and their obvious tri-layer multiple-chamber structures. X-ray diffraction and Fourier transform infrared spectroscopy measurements demonstrated that the drug MTD presented in the fibers in an amorphous state and was compatible with the three polymeric matrices. In vitro dissolution tests verified that the three kinds of polymer could act in a synergistic manner for a prolonged sustained-release profile of MTD in the gut. The drug controlled-release mechanisms were suggested in detail. The protocols reported here pioneer a new route for creating a tri-layer core–shell structure from both aqueous and organic solvents, and a new strategy for developing advanced drug delivery systems with sophisticated drug controlled-release profiles. [ABSTRACT FROM AUTHOR]

The design and fabrication of nanomaterials with controllable morphology and size is of critical importance to achieve excellent catalytic performance in heterogeneous catalysis. In this work, cobalt oxide (Co3O4) nanostructures with different morphologies (nanoplates, microflowers, nanorods and nanocubes) were successfully constructed in order to establish the morphology–property–performance relationship of the catalysts. The morphology and structure of the nanostructured Co3O4 were characterized by various techniques, and the catalytic performance of the as-prepared nanostructures was studied by monitoring the reduction of p-nitrophenol to p-aminophenol in the presence of excess NaBH4. The catalytic performance was found to be strongly dependent on their morphologies. The experimental results show that the pseudo-first-order reaction rate constants for Co3O4 nanostructures with various shapes are, respectively, 1.49 min−1 (nanoplates), 1.40 min−1 (microflowers), 0.78 min−1 (nanorods) and 0.23 min−1 (nanocubes). The Co3O4 nanoplates exhibited the highest catalytic activity among the four nanostructures, due to their largest specific surface area, relatively high total pore volume, best redox properties and abundance of defect sites. The established correlation between morphology, property and catalytic performance in this work will offer valuable insight into the design and application of nanostructured Co3O4 as a potential non-noble metal catalyst for p-nitrophenol reduction. [ABSTRACT FROM AUTHOR]

Using InSb/GaSb semiconductor quantum dots, we demonstrate the lateral spatial resolution of scattering apertureless near-field microscope equal to 10 – 15 nm at a wavelength of λ = 10.7 μm provided by a single-mode CO2 laser. The measurement conditions make it possible to undoubtedly exclude any artifacts caused by the sample topography and other similar factors. We identify the strongly localized in-plane near-field signal with a two-dimensional electron gas clamped on the InSb/GaSb interface of quantum dots. [ABSTRACT FROM AUTHOR]

Thermoelectrics is an emerging technology in the field of renewable energy sources, and the exploration of doped materials has opened up new avenues for enhancing their performance. La-doped thermoelectric materials with the composition Bi2−xLaxTe3 (x = 0.0, 0.1, 0.2, 0.3, 0.4) were synthesized using the WOWS sol–gel method and sintered at 500 °C for 5 h. X-ray diffraction analysis confirmed a rhombohedral crystal structure with lattice constants of a = b = 4.41(2) Å and c = 29.81(3) Å. Scanning electron microscopy revealed particle-like shapes (0.7–2.5 μm). Fourier transform infrared spectroscopy confirmed the single-phase nature of the samples. DC electrical measurements showed increasing conductivity with temperature. AC electrical analysis demonstrated frequency-dependent behavior with increasing AC conductivity and decreasing loss factor and dielectric constants. Seebeck coefficient measurements exhibited temperature-dependent behavior. Thermal transport properties showed increasing thermal conductivity and volumetric specific heat with temperature, while thermal diffusivity decreased. The composition Bi1.9La0.1Te3 with x = 0.1 doping displayed lower thermal conductivity, higher electrical conductivity, and a higher ZT value, making it more suitable for thermoelectric applications. Furthermore, the sample Bi1.8La0.2Te3 exhibited favorable characteristics for energy storage applications compared to the other samples. These findings provide insights into the potential applications of La-doped bismuth telluride compounds in thermoelectric and energy storage systems. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC)-derived cobalt molybdophosphate (CMP) nanocomposite material was synthesized by sol-gel technique. The physico-chemical properties such as composition, functional groups, thermal stability, phase transition, and surface structure were characterized using TGA, FT-IR, SEM, and TEM analyses. Membranes from the nanocomposite material were prepared to elucidate the electrochemical properties. The ionic potential was measured using strong electrolytes such as KCl, NaCl, and LiCl. Electrolytes have the following cation-sequenced with observed membrane potentials Li+ > Na+ > K+. The estimated membrane charge density was calculated for membrane performance. Membrane characteristics, such as transport number, mobility ratio, and charge efficiency, were determined using the Teorell–Meyer–Sievers (TMS) theory framework. LiCl has the highest value of t+ and ω ¯ . The nanocomposite membrane is lithium cation-selective, which can, therefore, be effectively utilized in various electro-membrane processes such as lithium-ion extraction and removal. [ABSTRACT FROM AUTHOR]

Ferrites count among the most functionally versatile magnetic materials in use in high technologies. In this study, synthesis, characterization and assessment of potential for use in water remediation of two different types of nanostructured ferrites were performed. Barium hexaferrite (BaFe12O19, BHF) and strontium hexaferrite (SrFe12O19, SHF) nanoparticle preparation using a flash-combustion method was successful. The prepared samples were thoroughly characterized for their microstructure, morphology, elemental composition, functional groups, surface charge density and magnetic, dielectric and optical properties. The hexagonal phase was detected as the primary one in X-ray diffraction patterns, while vibrational spectrophotometry analyses demonstrated the presence of an M-type hexagonal structure. Temperature-dependent ferromagnetic behavior of the nanoparticles was indicated from the χ-T curves, with a slightly higher single transition temperature, Tc, for BHF than for SFH: 675 °C vs. 650 °C. Despite having nanocrystalline structures, both BHF and SHF were identified as hard magnetic materials, with saturation magnetizations of 56.7 and 54.3 emu/g, respectively, and anisotropy fields greater than 9 kOe. Finally, batch adsorption studies were used to remove Pb(II) ions from aqueous solutions at various pHs and contact times using the as-prepared materials as fresh sorbents. The highest adsorption capacity was achieved at pH 7 and after 60 min of the contact time, equivalent to 84% and 80% for BHF and SHF, respectively. Extrinsic microstructural factors, such as particle morphology, surface area and porosity, proved to be more important for promoting the sequestration of Pb(II) than the intrinsic, crystallographic factors. Consequently, BHF performed better as an adsorbent than SHF under all of the tested conditions. The investigated nanostructured hexaferrites also demonstrated an exceptional recycling capacity. [ABSTRACT FROM AUTHOR]

A simple and label-free bacteria-imprinted impedimetric (BIP) sensor for the sensitive measurement of Escherichia coli has been developed. The BIP sensor is fabricated by one-step electropolymerization of pyrrole (functional monomer), copper phthalocyanine-3, 4', 4'', 4'''-tetrasulfonic acid tetrasodium salt (CuPcTs, dopant), and target bacteria (E. coli O157:H7) on a glassy carbon electrode. After the removal of the bacterial template, the established imprinted sites on the CuPcTs-doped polypyrrole film (PPy/CuPcTs) enable the highly selective rebinding of target bacteria and the resulting impedance change of the sensing interface is used to detect the target bacteria. We found that during the electropolymerization process, CuPcTs induced pyrrole to form granular-like nanostructured PPy/CuPcTs with excellent conductivity compared with the PPy film, substantially improving the sensitivity of the proposed sensor. The sensor presented a wide detection range (102 ~ 107 CFU⋅mL-1, RSD 1.1% ~ 3.5%) with a limit of detection of 21 CFU⋅mL-1. Furthermore, the proposed sensor effectively distinguished E. coli O157:H7 from other non-target bacteria and exhibited good practicality with recoveries from 91 to 103% in spiked real samples, indicating the potential utility of the sensor in food safety and environmental monitoring. [ABSTRACT FROM AUTHOR]

An analysis of the nanostructure morphology of ionic carboxyl-containing phthalocyanine and tetrasodium salt of Cu(II)-phthalocyanine-tetrasulphonic acid in the structure of latex polymers is carried out using optical and quasi-optical methods: optical microscopy, atomic-force microscopy (AFM), and fluorescence and Raman spectroscopy. The variety of shapes and sizes of the phthalocyanine nanostructures localized in the interparticle space of the latex polymers is analyzed, which determines the difference in their photochemical properties. [ABSTRACT FROM AUTHOR]

This report systematically demonstrated the plasmonic and localized surface plasmon resonance (LSPR) effect in the perovskite solar cells (PSCs) using MAPbI3 as an active layer. The finite element method (FEM) was employed for the entire simulation of PSCs. Various light trapping and smooth charge carrier dynamics geometries with tailored nanoparticles (NPs) radius and core-shell thickness like Au NPs, Au@TiO2 core-shell, and Au@TiO2 nanorods (NR) were incorporated in the active layer. We observed their effect on PSC's optical absorption, charge carrier generation, and power conversion efficiency (PCE). The light absorption, generation rate, and short-circuit current density (JSC) were improved after embedding Au NPs with varying radii in the active layer. The best PCE achieved for Au NPs with a radius (AuNPs = 50 nm) was compared to the reference model without Au NPs (14.32 %). This increment in PCE is dedicated to the strong LSPR effect and improved JSC. The other cases, like Au@TiO2 core-shell and Au@TiO2 NR, also performed better than the reference model and Au NPs-based PSCs. The highest PCEs achieved for Au@TiO2 core-shell and Au@TiO2 NR were 16.52 % and 18.47 % Which is 15.53 %, and 28.98 %, higher than the reference model. This improvement in the performance of Au@TiO2 core-shell and Au@TiO2 NR-based PSCs is due to the strong LSPR effect, near-field enhancement, far-field scattering, increase in the generation rate of the exciton, and the overall performance of PSCs. These investigations contribute to further exploring the emerging technology of plasmonic-based PSCs and propose promising techniques to enhance photon energy and charge carrier dynamic management. [ABSTRACT FROM AUTHOR]

The diffusion technology has been developed for the formation of binary clusters involving elements of group III and V in silicon. It is shown that by controlling the concentration of elements of group III and V atoms, multilayer silicon-based heterojuns can be formed in the surface region of silicon with enriched AIIIBV nanocrystals, followed by enriched with various combinations of Si2AIIIBV unit cells (1 – 5 m thick). This creates a practical new material based on silicon - a continuous graded-gap structure, i.e. heterojunsby a smooth transition from the band gap of III – V semiconductor compounds to the band gap of silicon. [ABSTRACT FROM AUTHOR]

An approach that allows a qualitative and quantitative analysis of the grain structure of ultrafine grained nickel by electrochemical etching surface is proposed. The data on the etching relief of ultra-fine-grained nickel obtained by scanning tunneling microscopy are analyzed. The bimodality of the structure is revealed, which is confirmed by statistical analysis. [ABSTRACT FROM AUTHOR]

Nanostructured surfaces with dimensions on a scale of a few millimeters exhibit remarkable hydrophobicity. The geometry of these nanostructures considerably affects their wettability. However, determining the optimal geometry is challenging due to the abundance of geometry parameters and the difficulty in numerically describing their effects on wettability at the mesoscopic scale. In addition, the fabrication of nanostructured surfaces with precise geometries is challenging. We establish a lattice Boltzmann method (LBM) model to address these challenges. We use the model to gain mesoscopic insights into the interaction between droplets and nanostructures. Our model can accurately reproduce contact angles (CAs) on various nanostructured surfaces and enables investigation of the effects of nanostructure geometry on wettability. We optimize the geometry of the nanostructures using the insights provided by the LBM model on the wettability mechanisms. Our analysis indicates that cones with dimensions of 40 µm in width and 33 µm in height exhibit the highest hydrophobicity. We successfully fabricate a superhydrophobic surface with the desired geometry via laser scanning, achieving a CA of 163°. We believe that this approach, which combines the LBM model and laser manufacturing, will enable a better understanding of the wettability mechanism and provide a high-performance approach for fabricating superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

Due to many factors, the electrical explosion spraying process is not stable, which directly causes unstable coating quality and structure. Electron beam treatment may be used to improve the surface and modified structure of coatings sprayed by electrical explosions. In this study, a new TiB2–Ag metal matrix composite coating was deposited by electrical explosion spraying and modified by electron beam treatment. The prepared coatings were characterized by surface macro- and microanalysis, XDR, cross-section SEM, and TEM. The composition of the spray-coating phase differs from sample to sample. The electron beam treatment normalized the phase composition. Ag TiB2 B2O became the main phase in the modified coating. Increasing the pulse energy density and duration leads to a reduction in the low-melting Ag phase and the formation of copper contact phases due to heating and melting of the copper substrate by excess electron beam energy. The coating structure consists of a silver matrix and TiB2 inclusions. The electron beam treatment did not affect the structure; however, the microstructure of the coating transformed into a cellular crystallization structure. The silver matrix nanostructure was transformed into a nanocrystalline structure with an average crystal size ranging from tens to hundreds of nanometers. [ABSTRACT FROM AUTHOR]

Modern materials often have multicomponent alloys, whose properties are determined by their phase and structural composition formed as a result of previous thermomechanical processing. Therefore, the problem of managing the structural state occupies an important place in the overall strategy of developing new materials. Particular attention is drawn to phase transformations in ultrafine systems, in particular, in alloys subjected to severe plastic deformation. In this case, the sample size becomes an important parameter determining the physical properties of the substance and, in particular, its structural and phase compositions. Despite the considerable interest of researchers, until recently, it was not possible to achieve significant theoretical results in this area. Therefore, the development of modern models for describing structural transformations in heterogeneous systems and their application to ultrafine-grained materials seem promising and relevant. [ABSTRACT FROM AUTHOR]

Optical absorption spectra of GaSb/GaAs quantum-ring-with-dot structures (QRDSs) are calculated using Fermi's golden rule by which the electronic states involved in the optical transitions are obtained from the eight-band k ⋅ p method. The absorption spectra of multi-stacked QRDS layers show that the interband and intraband transitions are favorable to intermediate band solar cells (IBSCs). A drift-diffusion model with rate equations for a solar cell containing multi-stacked QRDS layers is formulated based on the absorption spectra. The external quantum efficiency (EQE) determined by the model with the AM1.5 solar spectrum and additional infrared light demonstrates that the confined hole states in the quantum ring (QR) parts of the QRDSs effectively function as an IB. The more efficient two-step photon absorption indicated by the enhancement of the EQE also suggests the potential of QRDSs for the IBSCs. [ABSTRACT FROM AUTHOR]

Fe 2 O 3 is an appealing anode material due to its high specific capacity (1007 mAh g−1), low cost, natural abundance, and nontoxicity. However, its unstable structure during cycling processes has hindered its potential. In this study, we present a "green" synthesis method to fabricate stable porous Fe 2 O 3 encapsulated in a buffering hollow structure (p -Fe 2 O 3 @ h -TiO 2) as an effective anode material for Li-ion batteries. The synthesis process only involves glucose as an "etching" agent, without the need for organic solvents or difficult-to-control environments. Characterizations of the nanostructures, chemical compositions, crystallizations, and thermal behaviors for the intermediate/final products confirm the formation of p -Fe 2 O 3 @ h -TiO 2. The synthesized Fe 2 O 3 anode material effectively accommodates volume change, decreases pulverization, and alleviates agglomeration, leading to a high capacity that is over eleven times greater than that of the as-received commercial Fe 2 O 3 after a long cycling process. This work provides an attractive, "green" and efficient method to convert commercially abundant resources like Fe 2 O 3 into effective electrode materials for energy storage systems. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the thermochromic characterizations of VO 2 thin films synthesized by the thermal oxidation method. The oxidation process of a DC sputtered metallic vanadium layer on glass substrates, at 450 °C for 1 h, was carried out in the presence of CO 2 :N 2 gases with different flux ratios of 30:70, 40:60, 50:50, 60:40, and 70:30, respectively. Using CO 2 , as the oxidizing gas, provides an easy control route for obtaining the VO 2 phase among various vanadium oxide phases. The layers were characterized by FESEM, XRD & Raman spectra, sheet resistance vs. temperature (20–120 °C), and UV–Vis–NIR spectra at 25 and 90 °C. The XRD and Raman spectra confirmed all prepared layers have a VO 2 polycrystalline structure in monoclinic phase. We found among the studied samples CN30-70 and CN50-50 having desirable optical characteristics of peak visible transmittance of about 55%, with low transition temperatures (T cr) of ∼42 and 31 °C, and also relatively high amounts of ΔT 1700nm , ΔT sol and T lum,av are good candidates for thermochromic smart windows, both from optical properties and economical fabrication method points of view. [ABSTRACT FROM AUTHOR]

In order to solve the leakage and distinct super cooling issues of polyethylene glycol (PEG), zinc polyacrylate was used as the supporting material to prepare PEG‐based form‐stable phase change materials (FSPCMs) in this paper. The polyacrylate fractions of zinc polyacrylate are crosslinked by zinc ions through electrovalent bonding. Due to the strong intermolecular force between PEG molecules and the crosslinked polyacrylate fractions, the PCMs have stabilized shape even at 90°C. Zinc ions will gather together because of the incompatibility between PEG matrix and zinc ions, to form nanostructure as the nucleating agent of PEG, weakening the supercooling of the FSPCMs. The enthalpy change values of the FSPCMs in the phase transition processes are all above 120.0 J g−1, showing good thermal energy storage capacity. Additionally, the FSPCMs after 100 times of thermal cycling possess similar thermal properties to the original ones, indicating that the nanostructured zinc polyacrylate has stable interaction with the PEG matrix. [ABSTRACT FROM AUTHOR]

Different types of superhydrophobic materials have been fabricated by constructing surfaces with low surface energy and micro-nanostructures, most of which are coatings. Due to the fragile rough structure of the coating, it is very easy to lose its superhydrophobic properties when exposed to friction, corrosion, high temperature, and other effects of the external environment. This has largely hindered the large-scale application of superhydrophobic materials. Here, a rigid superhydrophobic material with polyurethane foam as the substrate, polytetrafluoroethylene (PTFE) nanoparticles as the matrix phase, and carbon nanotubes as the reinforcing phase have been reported. The fabricated material showed excellent superhydrophobicity (157∘ ± 1∘) and robustness. The contact angle of the superhydrophobic material surface remained above 150∘ and the rolling angle below 10∘ after 1000 cycles (distance is 40 m) of abrasion using 800 # sandpaper at pressure of 5 kPa. [ABSTRACT FROM AUTHOR]

The sensitivity of the metal–oxide–semiconductor‐type gas sensors has been improved typically using novel metal catalysts, such as Pt, Ru, and Pd. However, the sensing performance could be enhanced by only controlling the nanostructure. Herein, we introduce fabrication methods for ZnO nanobelt by changing the supply rate of hydroxide ions. Hexamethylenetetramine (HMT) and potassium hydroxide were used to generate hydroxide ions, and their rate to reach the maximum pH was different by more than twofold. The supply rate of hydroxide ions caused the different morphology of ZnO nanomaterial due to the change in the seed of material formation. Although both samples could detect acetone gas up to 100 ppt, ZnO nanobelts synthesized by HMT exhibited higher sensitivity. The ZnO morphology influenced the exposed surface area, and a larger specific surface area could facilitate the generation of pre‐adsorbed oxygen species that are the main factor for sensitivity. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures as narrowband perfect absorbers have garnered significant attention due to their potential applications in biosensing and environment detection. This study emphasizes the investigation of arrayed split ring nanostructures within the configuration of metal-insulator-metal (MIM) multilayers, resulting in a maximum light absorption of 99.94% in the near-infrared (NIR) spectral range. The exceptional absorption efficiency of the device is attributed to the strong resonance of electric and magnetic fields arising from the Fabry–Pérot cavity resonance. The resonant peak can be flexibly tuned by engineering the dielectric layer thickness, the period, and the geometric parameter of split rings. Remarkably, the device exhibits promising capabilities in sensing, demonstrating a sensitivity of 326 nm/RIU in visible wavelengths and 504 nm/RIU in NIR wavelengths when exposed to bio-analytes with varying refractive indices. This designed nanostructure can serve as a promising candidate for biosensors or environmental detection. [ABSTRACT FROM AUTHOR]

In this work, we have achieved an advancement by integrating wide-angle capacity into vortex beams with an impressive topological charge (TC) of 12. This accomplishment was realized through the meticulous engineering of a propagation-phase-designed metasurface. Comprising gallium nitride (GaN), meta-structures characterized by their high-aspect ratio, this metasurface exhibits an average co-polarization transmission efficiency, reaching a remarkable simulated value of up to 97%. The intricate spiral patterns, along with their respective quantification, have been meticulously investigated through tilt-view scanning electron microscopy (SEM) and were further analyzed through the Mach–Zehnder interferometer. A captivating revelation emerged, a distinctive petal-like interference pattern manifests prior to the metasurface's designed focal distance. The occurrence of this petal-like pattern at a specific z-axis position prompts a deliberate manipulation of the helicity of the spiral branches. This strategic helicity alteration is intrinsically tied to the achievement of a minimized donut diameter at the designed focal length. In regard to the angular capability of the device, the captured images continuously showcase prominent attributes within incident angles spanning up to 30 degrees. However, as incident angles surpass the 30-degree threshold, the measured values diverge from their corresponding theoretical projections, resulting in a progressive reduction in the completeness of the donut-shaped structure. [ABSTRACT FROM AUTHOR]

Ultra-thin solar cells enable materials to be saved, reduce deposition time, and promote carrier collection from materials with short diffusion lengths. However, light absorption efficiency in ultra-thin solar panels remains a limiting factor. Most methods to increase light absorption in ultra-thin solar cells are either technically challenging or costly, given the thinness of the functional layers involved. We propose a cost-efficient and lithography-free solution to enhance light absorption in ultra-thin solar cells—a Tsuchime-like self-forming nanocrater (T-NC) aluminum (Al) film. T-NC Al film can be produced by the electrochemical anodization of Al, followed by etching the nanoporous alumina. Theoretical studies show that T-NC film can increase the average absorbance by 80.3%, depending on the active layer's thickness. The wavelength range of increased absorption varies with the active layer thickness, with the peak of absolute absorbance increase moving from 620 nm to 950 nm as the active layer thickness increases from 500 nm to 10 µm. We have also shown that the absorbance increase is retained regardless of the active layer material. Therefore, T-NC Al film significantly boosts absorbance in ultra-thin solar cells without requiring expensive lithography, and regardless of the active layer material. [ABSTRACT FROM AUTHOR]

Objectives: Nano-modified surfaces for dental implants may improve gingival fibroblast adhesion and antibacterial characteristics through cell-surface interactions. The present study investigated how a nanocavity titanium surface impacts the viability and adhesion of human gingival fibroblasts (HGF-1) and compared its response to Porphyromonas gingivalis with those of marketed implant surfaces. Material and methods: Commercial titanium and zirconia disks, namely, sandblasted and acid-etched titanium (SLA), sandblasted and acid-etched zirconia (ZLA), polished titanium (PT) and polished zirconia (ZrP), and nanostructured disks (NTDs) were tested. Polished titanium disks were etched with a 1:1 combination of 98% H2SO4 and 30% H2O2 (piranha etching) for 5 h at room temperature to produce the NTDs. Atomic force microscopy was used to measure the surface topography, roughness, adhesion force, and work of adhesion. MTT assays and immunofluorescence staining were used to examine cell viability and adhesion after incubation of HGF-1 cells on the disk surfaces. After incubation with P. gingivalis, conventional culture, live/dead staining, and SEM were used to determine the antibacterial properties of NTD, SLA, ZLA, PT, and ZrP. Results: Etching created nanocavities with 10–20-nm edge-to-edge diameters. Chemical etching increased the average surface roughness and decreased the surface adherence, while polishing and flattening of ZrP increased adhesion. However, only the NTDs inhibited biofilm formation and bacterial adherence. The NTDs showed antibacterial effects and P. gingivalis vitality reductions. The HGF-1 cells demonstrated greater viability on the NTDs compared to the controls. Conclusion: Nanocavities with 10–20-nm edge-to-edge diameters on titanium disks hindered P. gingivalis adhesion and supported the adhesion of gingival fibroblasts when compared to the surfaces of currently marketed titanium or zirconia dental implants. Clinical relevance: This study prepared an effective antibacterial nanoporous surface, assessed its effects against oral pathogens, and demonstrated that surface characteristics on a nanoscale level influenced oral pathogens and gingival fibroblasts. Clinical trial registration: not applicable [ABSTRACT FROM AUTHOR]

Thermo-catalytic decomposition (TCD) activity and stability depend upon the initial carbon catalyst structure. However, further transitions in the carbon structure depend on the carbon material (structure and composition) originating from the TCD process. In this article, reaction data are presented that illustrates the time-dependent TCD activity as TCD-formed carbon contributes and then dominates conversion. A variety of initial carbon catalysts are compared, including sugar char, a conductive carbon black (AkzoNobel Ketjenblack), a rubber-grade carbon black (Cabot R250), and its graphitized analogue as formed and partially oxidized. Regeneration of carbon catalysts by partial oxidation is evaluated using nascent carbon black as a model, coupled with subsequent comparative TCD performance relative to the nascent, non-oxidized carbon black. Activation energies for TCD with nascent and oxidized carbons are evaluated by a leading-edge analysis method applied to TCD. Given the correlation between nanostructure and active sites, two additional carbons, engine soots, are evaluated for regeneration and dependence upon nanostructure. Active sites are quantified by oxygen chemisorption, followed by X-ray photoelectron spectroscopy (XPS). The structure of carbon catalysts is assessed pre- and post-TCD by high-resolution transmission electron microscopy (HRTEM). Last, energy dispersive X-ray analysis mapping (EDS) is carried out for its potential to visualize oxygen chemisorption. [ABSTRACT FROM AUTHOR]

Cerium dioxide/graphene (CeO2/G) nanocomposites with different weight ratios were synthesized by hydrothermal method. The composition and structure of the composites were analyzed by X-ray diffractometer, Xphotoelectron spectroscopy, infrared spectrometer and scanning electron microscope. The effects of different weight ratios on the tribological properties of the samples were studied by using a four-ball tribometer, and the surface abrasion marks of the small rigid ball were characterized by scanning electron microscope. The results showed that CeO2 nanoparticles were uniformly loaded onto the graphene sheets and acted as spacers to prevent the sheets from being aggregated again. Under the conditions of friction loading 392 N and rotating speed 1 200 i/min, when the sample with the same mass fraction (0. 5%) is added, the sample with the weight ratio of 1: 8 of graphene and cerium nitrate has better antifriction and anti-wear performance, which can reduce the lubricating oil friction coefficient by 49% and the wear spot diameter by 20%. [ABSTRACT FROM AUTHOR]

Basic copper chloride (Cu 2 (OH) 3 Cl) microspheres with different surface nanostructure were synthesized via the dissolution regulation of calcite in CuCl 2 solution. We studied the influence of CuCl 2 concentration, reaction time and reaction temperature on the formation of Cu 2 (OH) 3 Cl, and the products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy and transmission electron microscopy. The concentration of CuCl 2 has a great influence on the dissolution rate of calcite, dispersed microsphere particles assembled by nano-blocks formed in 20 mM CuCl 2 solution. The surface of Cu 2 (OH) 3 Cl microsphere change from nano-block to nano-rod with increasing the reaction time from 20 min to 2 h Cu 2 (OH) 3 Cl microspheres with surface structure changed from nano-sheet, nano-plate to nano-block with the reaction temperature increase from 37 °C to 70 °C. The Cu 2 (OH) 3 Cl microsphere also displays superior antibacterial properties against S. aureus and E. coli. This work displays a new strategy to synthesize functional materials by the use of dissolution regulation methods. [ABSTRACT FROM AUTHOR]

Today, there is a sharp struggle for demanded and competitive products all over the world. The existing traditional production technologies have exhausted their possibilities. New technologies should be based on high energy technologies. One of such technologies is plasma technologies. Among the plasma technologies for hardening metal surfaces, the most suitable is the hardening technology using electric spark discharges. However, these technologies do not currently have process optimization. This article proposes one of the options for solving this problem by simulating the process of electrospark alloying of elements of refractory materials into the surface layer of samples of real parts of machines and mechanisms, which are models of these parts. [ABSTRACT FROM AUTHOR]

Developing the high-capacity anode materials such as conversion-type metal oxides which possess both Li and Na storage activity is very practical for the high-energy Li-ion battery (LIB) and Na-ion battery (LIB). Herein, we use NiCo2O4 anodes as a model to investigate the morphology evolution which accounts for the poor cycling performance and understand the effect of structure optimization on the electrochemical performance. Three NiCo2O4 samples with different morphologies of microspheres, nanospheres and nanosheets are synthesized. Firstly, the serious structural degradation of NiCo2O4 microspheres is observed whether it works as a LIB or SIB anode. In addition, a significant difference between the lithiation and sodiation capacity of NiCo2O4 materials reveals Na+ ions only partially intercalated in NiCo2O4 and the conversion reaction limited by the strain. Next, NiCo2O4 nanosheets on Ni foam as a binder-free anode for the LIB are investigated which suggest the positive effect of 3D nanostructures on the morphology stability. As a result, NiCo2O4 nanosheets deliver a high lithiation capacity of 1092 mAh g−1 after 100 cycles at 0.5 A g−1 and an excellent rate capacity of 643 mAh g−1 at 4 A g−1. Finally, NiCo2O4 nanospheres are evaluted as a SIB anode which indicate the smaller particle size of active materials is beneficial to the release of stress and structure stability during discharge–charge processes. Relatively speaking, the nano sheet structure is with the best electrochemical performance based on the capacity retention. A rational design of the electrode' architecture is very important for the conversion-type 3d transition metal oxide anodes for the advanced LIB and SIB. [ABSTRACT FROM AUTHOR]

Stacking atomically thin two-dimensional nanosheet materials leads to unique synergy in their inherent properties due to an intimate combination and matching that is not possible via separate individual components and phases. However, traditional synthesis and assembly methods result in poor architectural control, diffuse interfaces and restricted surface chemistry, thereby limiting their prospective potentials. This brief overview provides condensed consideration of different synthesis and assembly methods for the fabrication of diverse novel heterostructures from individual nanosheets and challenges of existing methods. Finally, future perspectives regarding crafting of well-defined heterostructures with highly controllable architectures and interfacial/surface chemistry and advanced characterization methods are highlighted. The combination of in-situ growth synthesis with precise compositional and interfacial chemistry control, and in-depth characterization enables the understanding and new developments of two-dimensional heterostructured architectures with programmed organization and enhanced properties for a variety of critical materials applications. [ABSTRACT FROM AUTHOR]

The major challenge of hydrogen production via photocatalytic water-splitting is to utilize active photocatalysts that respond to a wide range of visible light. In this work, hybrid nanostructures purposed to combine the tunable magnetic behavior of soft/semi-hard magnetic particles have shown advantageous photoactivity. A series of photocatalysts based on ferrite nanoparticles, magnetite nanoparticles (MNPs), cobalt ferrite nanoparticles (CFNPs), magnetite nanoparticles coated on cobalt ferrite nanoparticles (MNPs @ CFNPs), and cobalt ferrite nanoparticles coated on magnetite nanoparticles (CFNPs @ MNPs) were prepared. The size, morphology, magnetic properties, and optical activity of the prepared nanoparticles were characterized using multiple techniques. CFNPs @ MNPs had the largest particle size (~14 nm), while CFNPs had the smallest (~8 nm). The saturation magnetization of CFNPs @ MNPs was the highest at 55.45 emu g−1. The hydrogen yield was 60, 26, 3.8, and 93 mmole min−1 g−1 for MNPs, CFNPs, MNPs @ CFNPs, and CFNPs @ MNPs. CFNPs @ MNPs displayed a superior photocatalytic performance for hydrogen production under the magnetic force as appropriate materials for water-splitting processing. [ABSTRACT FROM AUTHOR]

A novel and universal method combining electrospinning with a twi-crucible fluorinating technology was utilized to fabricate one-dimensional LaF 3 :RE3+ (RE = Eu, Nd) nanostructured phosphors. A series of nanofibrous/nanoribbon-shaped LaF 3 :RE3+ (RE = Eu, Nd) phosphors were devised and facilely fabricated through the calcination of the relevant nanofibrous/nanoribbon-shaped La 2 O 3 :RE3+ (RE = Eu, Nd) precursors in air by applying a twi-crucible fluorinating method utilizing NH 4 HF 2 as a fluorine source without additional usage of reducing gas and protective gas. Nanofibrous/nanoribbon-shaped La 2 O 3 :RE3+ (RE = Eu, Nd) precursors were synthesized by calcinating the electrospun nanofibrous/nanoribbon-shaped [RE(NO 3) 3 +La(NO 3) 3 ]/polyvinyl pyrrolidone (PVP) composites. Nanofibrous/nanoribbon-shaped LaF 3 :RE3+ (RE = Eu, Nd) phosphors possess hexagonal structures with a space group of P 6 3 / mmc. Nanofibrous LaF 3 :RE3+ (RE = Eu, Nd) phosphors present excellent fibrous morphology with a uniform diameter of 131–143 nm. Nanoribbon-shaped LaF 3 :Eu3+ phosphors with 94.5 nm in thickness and 5.1 ± 0.4 μm in width were acquired. Nanoribbon-shaped LaF 3 :Nd3+ phosphors have a thickness of 179 nm and a width of 4.2 ± 0.4 μm. Upon excitation by ultraviolet light at 396 nm, nanofibrous/nanoribbon-shaped LaF 3 :Eu3+ phosphors emit the main emission band at approximately 591 nm, corresponding to the 5D 0 →7F 1 magnetic dipole transition of Eu3+. With an increment of Eu3+ concentration, the fluorescent strength of nanofibrous LaF 3 :Eu3+ phosphors is improved greatly and achieves a maximum when the Eu3+ concentration is approximately 5 mol%. Moreover, the nanofiber/nanoribbon-shaped LaF 3 :Eu3+ phosphors emit a yellow color. For Nd3+-doped phosphors, nanofibrous/nanoribbon-shaped LaF 3 :Nd3+ phosphors possess near-infrared optical performances, and the main emission peak is at 854 nm, corresponding to the 4F 3/2 → 4I 9/2 transition of Nd3+. The luminescence intensity of LaF 3 :Nd3+ phosphors decreases significantly with increasing Nd3+ content and reaches a maximum at 5 mol% Nd3+. The corresponding formative mechanisms of nanofibrous/nanoribbon-shaped RE3+ (RE = Eu, Nd) phosphors are expounded, and the corresponding construction technique is established. The new findings in this work lay a foundation for wide applications of rare earth fluoride one-dimensional nanostructures. [Display omitted] • 1D LaF 3 :RE3+ nanostructure is made by electrospinning with twi-crucible fluorinating. • Nanostructures include nanofibrous and nanoribbon-shaped LaF 3 : RE3+ phosphors. • Different nanostructures are facilely obtained by modulating spinning parameters. • Luminescent intensity can be tunable by variation of Eu3+/Nd3+ concentrations. • Possible forming mechanisms of LaF 3 : Eu3+/Nd3+ 1D nanostructures are advanced. [ABSTRACT FROM AUTHOR]

Silicon‐based materials are among the most promising anode materials for next‐generation lithium‐ion batteries. However, the volume expansion and poor conductivity of silicon‐based materials during the charge and discharge process seriously hinder their practical application in the field of anodes. Here, we choose carboxymethyl chitosan (CMCS) as the carbon source coating and binding on the surface of nano silicon and hollow silicon dioxide (H−SiO2) to form a hierarchical buffered structure of nano‐hollow SiOx@C. The hollow H−SiO2 can alleviate the volume expansion of nano silicon during the lithiation process under continuous cycling. Meanwhile, the carbon layer carbonized by CMCS containing N‐doping further regulates the silicon's expansion and improves the conductivity of the active materials. The as‐ prepared SiOx@C material exhibits an initial discharge capacity of 985.4 mAh g−1 with the decay rate of 0.27 % per cycle in 150 cycles under the current density of 0.2 A g−1. It is proved that the hierarchical buffer structure nano‐hollow SiOx@C anode material has practical application potential. [ABSTRACT FROM AUTHOR]

Cubosomes have aroused growing interest recently due to their widespread applications in pharmaceutical, food, cosmetic industries, etc. Especially, they demonstrate many advantages as drug delivery systems. However, no pharmaceutical products have been translated from bench to bedside so far. To promote the translation of the drug delivery system candidate, it is significant to accumulate fundamental and applied-fundamental knowledge of cubosomes. In the study, a bibliometric study upon cubosome research was carried out on the basis of Web of Science Core Collection database to figure out current and evolving knowledge domains of the published studies in a logical and robust way, summarizing the status quo and pointing out the future directions of cubosome research. Four questions which are pending addressed were answered by applying this research method and some conclusions were drawn: (1) Australia could be viewed as the most productive contributor for cubosome research. (2) Langmuir might be the most influential publishing media. (3) Using cubosomes as drug delivery carriers was a hot topic. (4) Adopting cubosomes as ocular drug delivery vehicles would continue to be a frequently studied aspect. In addition, cubosomes serve as alternative vector deliver active pharmaceutical ingredients to the brain and encapsulate active components extracted from herbal and traditional medicines in cubosomes are the burgeoning trends. By answering the four questions, productive contributors, influential publishing media, current research foci, and future directions were figured out. Hence, the current and evolving knowledge domains of cubosome studies were illustrated. [ABSTRACT FROM AUTHOR]

[Display omitted] The origins and behaviour of specific ion effects have been studied in water for more than a century, and more recently in nonaqueous molecular solvents. However, the impacts of specific ion effects on more complex solvents such as nanostructured ionic liquids remains unclear. Here, we hypothesise that the influence of dissolved ions on the hydrogen bonding in the nanostructured ionic liquid propylammonium nitrate (PAN) constitutes a specific ion effect. We performed molecular dynamics simulations of bulk PAN and 1–50 mol% PAN-PAX (X = halide anions F−, Cl−, Br−, I−) and PAN-YNO 3 (Y = alkali metal cations, Li+, Na+, K+ and Rb+) solutions to investigate how monovalent salts influence the bulk nanostructure in PAN. The key structural characteristic in PAN is a well-defined hydrogen bond network formed within the polar and non-polar domains in its nanostructure. We show that dissolved alkali metal cations and halide anions have significant and unique influences on the strength of this network. Cations (Li+, Na+, K+ and Rb+) consistently promote hydrogen bonding in the PAN polar domain. Conversely, the influence of halide anions (F−, Cl−, Br−, I−) is ion specific; while F− disrupts PAN hydrogen bonding, I− promotes it. The manipulation of PAN hydrogen bonding therefore constitutes a specific ion effect – i.e. a physicochemical phenomena caused by the presence of dissolved ions, which are dependent on these ions' identity. We analyse these results using a recently proposed predictor of specific ion effects developed for molecular solvents, and show that it is also capable of rationalising specific ion effects in the more complex solvent environment of an ionic liquid. [ABSTRACT FROM AUTHOR]

Transparent ceramic is a kind of inorganic nonmetallic material with broad application prospects. However, the traditional preparation strategy based on powder sintering has technical limitations of relying on high-quality raw material powder, requiring long time high temperature treatment, complex equipment and process, and high production cost. Glass crystallization is a new method to achieve full crystallization of glass and obtain transparent ceramics by controlling the crystallization process. This method can overcome the technical difficulties associated with the traditional transparent ceramic processing. Meanwhile, it also shows unique advantages in preparing high density, pore-free, non-cubic phase, nanostructured transparent ceramics and has attracted significant attention. In this paper, the development and research status of glass crystallization method were reviewed in detail from two aspects: fully glass-crystallization of oxide transparent ceramics and related component systems. Then, the problems existing in the current research were pointed out, and the future development prospects were prospected. It is expected that this method can be widely used to prepare the next generation of high performance transparent ceramic materials. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of diabetes mellitus (DM) on the nanostructure of root canal dentin using high-resolution transmission electron microscopy (HRTEM) and inductively coupled plasma mass spectrometry (ICP-MS). Twenty extracted human premolars from diabetic and nondiabetic patients (n = 10 in each group) were decoronated and sectioned horizontally into 40 2-mm-thick dentin discs, with each disc designated for a specific test. ICP-MS was used to determine the different elemental levels of copper, lithium, zinc, selenium, strontium, manganese, and magnesium in diabetic and nondiabetic specimens. HRTEM was used to analyze the shape and quantity of the apatite crystals in diabetic and nondiabetic dentin at the nanostructural level. Statistical analysis was performed using Kolmogorov-Smirnov and Student t test (P <.05). ICP-MS revealed significant differences in trace element concentrations between the diabetic and nondiabetic specimens (P <.05), with lower levels of magnesium, zinc, strontium, lithium, manganese, and selenium (P <.05), and higher levels of copper in diabetic specimens (P <.05). HRTEM revealed that diabetic dentin exhibited a less compact structure with smaller crystallites and significantly more crystals in the 2500 nm2 area (P <.05). Diabetic dentin exhibited smaller crystallites and altered elemental levels more than nondiabetic dentin, which could explain the higher root canal treatment failure rate in diabetic patients. [ABSTRACT FROM AUTHOR]

Due to their individual plastic deformation behavior and mechanistic performances, gradient nano-grained (GNG) metals have been identified as promising materials for application in advanced engineering applications. However, their plasticity mechanism has not been thoroughly investigated. Hence, in this work, molecular dynamics simulation was employed to characterize the atomistic behavior of copper GNG structures under tensile loading with different grain sizes (2–9 nm) at varied temperatures (100, 300, and 600 K). The results indicated that there existed a critical grain size value (6 nm) for the Hall–Petch and inverse Hall–Petch relationship. Besides, it was found that the high-temperature loading (600 K) negatively affected the plasticity-induced strengthening, while low-temperature loading induced outstanding plasticity-induced strengthening owing to the excessive strain hardening events. The details of plastic deformation from the perspective of grain boundary, deformation twining, stacking faults, and dislocations were analyzed and a thorough discussion was presented to elucidate the grain size and temperature effects on the plasticity mechanism. [ABSTRACT FROM AUTHOR]

Resistance of bacteria to antibiotics is a serious human concern since it affects medical treatments performance against bacterial infections. Within the scope of new robust antibiotics development, we propose a heterocyclic–clay composite material. It consists of the association of 5-(2 pyridyl)-1-3-4-oxadiazoles-2-thione with pre-treated montmorillonite (MMT). Different pre-treatments were considered including acidification (H+-MMT) and intercalation with polar polymers facilitating the antibacterial composite material synthesis. The different composite materials that vary in terms of oxadiazole concentration were characterized in terms of structure (molecular, crystalline) using FTIR and XRD, and antibacterial properties. The obtained results showed successful intercalation of polar polymeric materials within acidified montmorillonite clay. The final composite material showed very promising antibacterial properties with reference to two well established antibiotics i.e., Penicillin and Spiramycine. The highest performance was observed for the composite containing polyvinyl alcohol intercalating the acidified montmorillonite with 50 wt % of 1,3,4-oxadiazole compound. [ABSTRACT FROM AUTHOR]

Semiconductor nanowhiskers, particularly nanostructured whiskers based on zero-dimensional (0D) C70 fullerene, are being actively discussed due to the great potential of their application in modern electronics. For the first time, we proposed and implemented a method for the synthesis of nanostructured C70 fullerene whiskers based on the self-organization of C70 molecules during the thermal evaporation of C70 droplets on the substrate surface. We found that the onset of the synthesis of C70 nanowhiskers upon the evaporation of drops of a C70 solution in toluene on the substrate surface depends on the substrate temperature. We have provided experimental evidence that an increase in both the C70 concentration in the initial drop and the substrate temperature leads to an increase in the geometric dimensions of C70 nanowhiskers. The obtained results provide useful vision on the role of solute concentration and substrate temperature in the synthesis of one-dimensional materials. [ABSTRACT FROM AUTHOR]

Background: The shortage of clean energy has become a serious problem due to the rapid development of societies and the increasing consumption of fossil fuels. Metal oxide semiconductor nanomaterials have been studied as photo‐/electrocatalysts for water splitting in terms of clean energy generation. Applications of semiconductors depend on their electronic structures. Therefore, elucidating the electronic diagram is essential for determining the specific applications of novel semiconductors. Results: Herein, we demonstrate using a combination of UV–visible diffuse reflectance spectroscopy (DRS) and Mott–Schottky analysis via electrochemical impedance spectroscopy for sketching the electronic diagram of nanostructured cobalt titanate (CoTiO3) prepared by the sol–gel method. UV–visible DRS studies reveal a band gap of 2.5 and 2.1 eV for direct and indirect transitions of prepared nanostructured materials, respectively. Mott–Schottky analysis shows a 0.8 V versus Ag/AgCl value for the flat band potential for CoTiO3. We further show the application of this diagram toward the interpretation of the electrochemical behavior of nanostructured CoTiO3 for electrochemical water splitting reactions and the electrochemical CO2 reduction reaction (eCO2RR). Conclusion: The presented electrochemical and photoelectrochemical studies demonstrate nanostructured CoTiO3 as an effective catalyst for electrochemical water oxidation and the eCO2RR. Moreover, our results provide valuable information for further investigation of water splitting and photovoltaic energy conversion. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

In this study, cadmium telluride (CdTe) thin films were prepared by conventional spray pyrolysis on glass substrates at different temperatures (250°C, 300°C, and 350°C). Field-emission scanning electron microscopy (FESEM) images demonstrated that the substrate temperature significantly affected the morphology and thickness of the grown layers. The Seebeck effect measurements showed that all the studied layers had p-type conductivity. X-ray diffraction and Raman spectroscopy results indicated that the layer grown at 350°C had better CdTe crystalline quality, although it still contained secondary oxide phase components (TeO2, TeO3, and CdTeO3), consistent with the analysis of electrical resistance versus temperature data. To eliminate oxide phase components in this sample, we used the annealing process in the presence of N2 gas flux for 1 h at two different temperatures, 400°C and 450°C. It was found that annealing at 400°C, the optimum annealing temperature, achieved the goal of eliminating secondary oxide phase components. [ABSTRACT FROM AUTHOR]

Using the sonochemical method, nano-plates of a 3D Zn(II) metal−organic framework (MOF) were synthesized and characterized using FT-IR spectroscopy and PXRD. The effect of various irradiation durations and concentrations of reagents was investigated to obtain uniform morphologies. Increasing the irradiation time along with decreasing the reagent concentration led to the production the particles with a uniform nano-plate morphology. Also, the sensing potential of these nano-plates to detect nitroaromatic analytes such as nitrophenol, 2,4-dinitrophenol, and TNP was explored. The nano Zn MOF was highly selective and sensitive in the detection of nitroaromatic derivatives. The quenching percentages of fluorescence emissions for a 2ppb concentration of nitrophenol, 2,4-dinitrophenol, and TNP were 11%, 42%, and 89%, respectively. According to the results, the MOF has the strongest detection limit for TNP. [ABSTRACT FROM AUTHOR]

In this study, the effect of strontium (Sr) concentration on the ultrafast humidity sensing performance of Sr doped zinc oxide (SrxZn1–xO) nanostructured thin films was reported. The sol gel method was used in the synthesis of undoped zinc oxide (ZnO) and SrxZn1–xO (x = 0.01, 0.02, 0.03, 0.04, and 0.10) nanoparticles. According to the x-ray diffraction analysis, all films had a hexagonal wurtzite structure. By doping Sr into the ZnO lattice, the preferential orientation changed from the (002) plane to the (101) plane. Scanning electron microscopy micrographs showed that all films had a structure containing nanosized grains and capillary-nanopores, and the nanosized grains were homogeneously and uniformly distributed on the surface of films. The presence of zinc, oxygen and Sr elements in nanostructured thin films was proved by energy dispersive x-ray spectra. The relative humidity sensing performances of undoped ZnO and SrxZn1–xO films were tested with electrical resistance measurements in the range of 40–90% RH at room temperature. SrxZn1–xO films had high sensitivity, excellent stability, reliable and reproducible character, and fast response and recovery times. Sr0.10Zn0.90O was accepted as the best sample in terms of having the highest humidity sensitivity (657.59x) and the fastest response (0.8 s) and recovery (9.8 s) times. This study clearly revealed that SrxZn1–xO nanostructured thin films have great potential for high performance humidity sensor applications due to their ultrafast humidity sensing performance. Highlights: Sol–gel method to synthesize Sr-doped ZnO nanoparticles. For RH-sensing performances, electrical resistance changes depending on %RH. Structural, morphological and elemental analyses with XRD, SEM and EDS. High-humidity sensitivity of 657.59x with Sr doping into ZnO. Ultra-fast response (0.8 s) and recovery (9.8 s) times with Sr doping into ZnO. [ABSTRACT FROM AUTHOR]

Silicon is a desirable anode material for Li-ion batteries owing to its remarkable theoretical specific capacity of over 4000 mAh/g. Nevertheless, the poor cycling performance of pure Si electrodes caused by dramatic volume expansion has limited its practical application. To alleviate the adverse effects of Si expansion, we have synthesized anode materials of nano-Si particles trapped in a buffering space and outer carbon-based shells (Si@Void@C). The volume ratio of Si nanoparticle to void space could be adjusted accurately to approximately 1:3, which maintained the structural integrity of the as-designed nanoarchitecture during lithiation/delithiation and achieved a notable specific capacity of ~750 mAh/g for as-prepared half-cells. The yolk-shell nanostructure alleviates volumetric expansion on both material and electrode levels, which enhances the rate performance and cycling stability of the silicon-based anode. [ABSTRACT FROM AUTHOR]

One of the approaches to improve the properties of polymers is to use additives in them. In the last few years, nanoscale additives have received attention due to the favorable properties they give to polymers in low concentrations. POSS or polyhedral oligomeric silsesquioxane has unique properties due to its nanometer size and organic–inorganic nature. The rigid structure of POSS and its compatibility with all types of polymers make their use attractive in various polymer industries. The concentration, structure of the mineral core, and type of POSS organic groups can affect the final properties of polymers containing these nanostructures. Chemical mixing of POSS with polymer increases the viscosity of the system, while physical mixing decreases the viscosity of the polymer. These nanostructures can improve properties such as tensile strength, modulus, and toughness of the polymer. Polymers with low concentrations of POSS have the advantage of high thermal stability and low flammability, which makes them ideal for applications in the aerospace industry where materials must withstand extreme temperatures and harsh environments. In addition, the low dielectric constant of POSS-containing polymers makes them useful for use in electronic components. The high specific surface of POSS allows the use of these nanostructures as supports for various catalysts. POSS is used in a wide range of industries including aerospace, biomedical, electronics and chromatography columns, etc. [ABSTRACT FROM AUTHOR]

A novel hierarchically nanostructured magnetite (Fe3O4) was manufactured using microwave-assisted reflux method without surfactants. The nanostructured Fe3O4 is formed via the co-precipitation of Fe(III) and Fe(II), followed by a nanocrystal aggregation-based mechanism. Moreover, the effects of solution pH, contact time, initial Sb concentration, coexisting anions, and recycle numbers on the adsorption of nanostructured Fe3O4 toward Sb were extensively examined in the batch adsorption tests. The results demonstrated that the obtained Fe3O4 exhibited excellent adsorption ability toward Sb with the maximum adsorption capacities of 154.2 and 161.1 mg.g−1 for Sb(III) and Sb(V), respectively. The prepared Fe3O4 could be easily regenerated and reused for adsorption/desorption studies multiple times without compromising the Sb adsorption ability. Further exploration indicated that the oxidation or reduction reactions infrequently occurred during Sb adsorption processes. The proposed hierarchically nanostructured Fe3O4 thus could be potentially used for sustainable and efficient antimony removal. [ABSTRACT FROM AUTHOR]