Search Results (290)

Under normal conditions, the novel zinc blende beryllium oxide (zb BeO) exhibits in a metastable crystalline phase, which is less stable than its wurtzite counterpart. Ultrathin zb BeO epifilms have recently gained significant interest to create a wide range of advanced high-resolution, high-frequency, flexible, transparent, nano-electronic and nanophotonic modules. BeO-based ultraviolet photodetectors and biosensors are playing important roles in providing safety and efficiency to nuclear reactors for their optimum operations. In thermal management, BeO epifilms have also been used for many high-tech devices including medical equipment. Phonon characteristics of zb BeO at ambient and high-pressure P ≠ 0 GPa are required in the development of electronics that demand enhanced heat dissipation for improving heat sink performance to lower the operating temperature. Here, we have reported methodical simulations to comprehend P-dependent structural, phonon and thermodynamical properties by using a realistic rigid-ion model (RIM). Unlike zb ZnO, the study of the Grüneisen parameter γ(T) and thermal expansion coefficient α(T) in zb BeO has revealed atypical behavior. Possible reasons for such peculiar trends are attributed to the combined effect of the short bond length and strong localization of electron charge close to the small core size Be atom in BeO. Results of RIM calculations are compared/contrasted against the limited experimental and first-principle data. Full article

Nowadays, nanosized mesoporous oxides are of increasing interest to scientists. They can be used as components of heterogeneous catalysts, for photo- and electrocatalysis, as gas sensors, etc. For instance, the desired properties in catalysts include a nano size and homogeneity of the particles that form the catalyst. The particle sizes of oxides are set at the initial stage of their formation, as precursors of precipitation in the context of wet chemistry. The creation of optimal conditions is possible through the use of homogeneous precipitation, where the precipitant is formed within the solution itself as a result of a hydrolysis reaction. The resolution of this issue involved the utilization of urea in our experimental setup, obtaining the hydrolysis products of ammonia and carbon dioxide. Consequently, precipitation reactions can be utilized to obtain hydroxides, carbonates, or hydroxy carbonates of metals. The precursors were calcined, obtaining nanosized mesoporous oxides, which can have a wide range of applications. Nanosized 0.1–50 nm metal oxides were obtained, including those aluminum, iron, indium, zinc, nickel, and cobalt. Full article

Brain ischemia is a severe condition caused by reduced cerebral blood flow, leading to the disruption of ion gradients in brain tissue. This imbalance triggers spreading depolarizations, which are waves of neuronal and glial depolarization propagating through the gray matter. Microelectrode arrays (MEAs) are essential for real-time monitoring of these electrophysiological processes both in vivo and in vitro, but their sensitivity and signal quality are critical for accurate detection of extracellular brain activity. In this study, we evaluate the performance of a flexible microelectrode array based on gold-coated zinc oxide nanorods (ZnO NRs), referred to as nano-fMEA, specifically for high-fidelity electrophysiological recording under pathological conditions. Acute mouse brain slices were tested under two ischemic models: oxygen–glucose deprivation (OGD) and hyperkalemia. The nano-fMEA demonstrated significant improvements in event detection rates and in capturing subtle fluctuations in neural signals compared to flat fMEAs. This enhanced performance is primarily attributed to an optimized electrode–tissue interface that reduces impedance and improves charge transfer. These features enabled the nano-fMEA to detect weak or transient electrophysiological events more effectively, making it a valuable platform for investigating neural dynamics during metabolic stress. Overall, the results underscore the promise of ZnO NRs in advancing electrophysiological tools for neuroscience research. Full article

Water scarcity poses a formidable challenge around the world, especially in arid regions where limited availability of freshwater resources threatens both human well-being and ecosystem sustainability. Membrane-based desalination technologies offer a viable solution to address this issue by providing access to clean water. This work ultimately aims to develop a novel permselective polymeric membrane material to be employed in an electrochemical desalination system. This part of the study addresses the optimization, preparation, and characterization of a polyvinylidene difluoride (PVDF) polymeric membrane using the electrospinning technique. The membranes produced in this work were fabricated under specific operational, environmental, and material parameters. Five different additives and nano-additives, i.e., graphene oxide (GO), carbon nanotubes (CNTs), zinc oxide (ZnO), activated carbon (AC), and a zeolitic imidazolate metal–organic framework (ZIF-8), were used to modify the functionality and selectivity of the prepared PVDF membranes. Each membrane was synthesized at two different levels of additive composition, i.e., 0.18 wt.% and 0.45 wt.% of the entire PVDF polymeric solution. The physiochemical properties of the prepared membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), zeta potential, contact angle, conductivity, porosity, and pore size distribution. Based on findings of this study, PVDF/GO membrane exhibited superior results, with an electrical conductivity of 5.611 mS/cm, an average pore size of 2.086 µm, and a surface charge of −38.33 mV. Full article

Structural color is a kind of natural color that widely exists in nature. The ordered microstructure of nano materials can absorb or reflect light of specific wavelength, thus showing colorful colors. Structural color is an ideal choice for color contact lens pattern pigment due to its good tinting degree, stability, and nontoxicity. This paper explores a method for synthesis of zinc oxide (ZnO) nanoparticles with a high refractive index and enhancement of the brightness of the structured colors by introducing carbon black nanoparticles. This method is convenient and successful to prepare ZnO ink, which can produce bright structural colors, and to produce color patterns through rubber pad printing. It is worth mentioning that ZnO nanoparticles can be self-assembled and arranged in contact lens ink without subsequent complicated processing. At the same time, the color only comes from ZnO and carbon black. While there is no other organic matter, the presence of nanoparticles plays a certain role in sterilization. Blue contact lenses prepared by this method have bright structural color, high oxygen permeability, and high hydrophilicity. At the same time, a cell viability test showed that the contact lenses prepared by this method had low adsorption capacity for lipids and proteins, reflecting the photonic crystal’s high biocompatibility. In summary, a trend for future research is to use high-refractive-index zinc oxide nanoparticles to produce structural colors rather than employing conventional contact lens pigments. Full article

Glycyrrhiza uralensis Fisch. is an important economic plant. With its wild populations on the brink of extinction and the area of salinized soil increasing sharply, farmers have gradually used saline soil to carry out artificial cultivation of the licorice. However, the salt stress has led to a significant decrease in the yield and quality of its medicinal organ (root), seriously restricting the sustainable development of the licorice industry. Therefore, we investigated zinc oxide nanoparticles (ZnO NPs) as a nano-fertilizer to enhance root biomass and bioactive compound accumulation under salinity. Our results indicate that under 160 mM NaCl stress, the application of 30 mg/kg ZnO NPs increased the root biomass of the licorice and the contents of glycyrrhizic acid, glycyrrhizin, and total flavonoids in the roots by 182%, 158%, 87%, and 201%, respectively. And the ZnO treatment made the enzyme activities of SOD, CAT, and POD exhibit increase, and made the levels of superoxide anions, electrolyte leakage, soluble sugar, and proline reduce. These results demonstrate that ZnO NPs not only enhance salt tolerance but also redirect metabolic resources toward medicinal compound biosynthesis. Our findings provide a mechanistic basis for utilizing nanotechnology to sustainably cultivate the licorice in marginal saline environments, bridging agricultural productivity and pharmacological value. Full article

In this study, we aimed to investigate the effects of coagulants and dissolved organic matter (DOM) on the biological toxicity of nano-zinc oxide (nZnO) to key microorganisms involved in biological phosphorus removal during sewage treatment. Polyaluminum chloride and polyferric chloride were selected as coagulants, whereas fulvic acid, glucose, and aspartic acid represented the DOM. The mechanisms through which these chemicals influence nZnO toxicity were also investigated. The results show that polyaluminum chloride and polyferric chloride effectively reduced nZnO toxicity in phosphorus-accumulating organisms, demonstrating their detoxification effects. Similarly, fulvic acid and glucose mitigated nZnO toxicity, whereas aspartic acid displayed dual effects: detoxification at low concentrations and enhanced toxicity at high concentrations. These findings highlight the dual role of sewage treatment additives in enhancing traditional pollutant removal and mitigating the nanoparticle-induced inhibition of microbial biochemical processes. This study clarified the interactions between coagulant chemicals, DOM, and nanoparticles in sewage treatment, offering insights into the regulatory mechanisms that improve treatment efficacy and reduce ecological risks. Full article

Transition metal oxide aerogels (AGLs) have attracted considerable attention in recent years due to their exceptional properties, including high surface area, significant porosity, and ultralow density. In this study, we report the first-time synthesis of zinc oxide nano-wafers and zinc aerogels for application as supercapacitor electrodes. The aerogels were synthesized via a novel one-pot hydrolysis method using NaBH₄ as a reducing agent and subsequently annealed at 200 °C (Zn_AGL(200)) and 450 °C (Zn_AGL(450)) to investigate the influence of temperature on their electrochemical properties. Structural and morphological characterizations were conducted using XRD, FTIR, BET, XPS, SEM, and TEM analyses. Among the fabricated electrodes, the aerogel annealed at 200 °C (Zn_AGL(200)) exhibited superior energy storage performance, attributed to its amorphous, continuous network structure, which enhanced its surface area and reduced its density compared to both the as-synthesized (Zn_AGL(RT)) and 450 °C-annealed (Zn_AGL(450)) counterparts. A two-electrode device demonstrated excellent cycling stability over 10,000 cycles, achieving an energy density of 7.97 Wh/kg and a power density of 15 kW/kg. These findings highlight the potential of zinc aerogels as materials for next-generation lightweight energy storage systems, with promising applications in industrial, mechanical, and aerospace technologies. Full article

In the current study, the Prussian blue analog decorated with zinc oxide (PBA@ZnO) was produced using a simple chemical co-precipitation method. The nanohybrid was examined using XRD, EDX, SEM, and TEM techniques, where it exhibited a polycrystalline structure with highly intense broadening peaks. The surface morphology was observed as thin nanosheets decorated with tiny spheres. Following excitation at 360 nm, the fluorescence spectra of PBA@ZnO showed fluorescence emission at 455 nm. The developed PBA@ZnO was used to qualitatively and quantitatively assess sunset yellow (SY), where its native fluorescence was selectively quenched as SY concentrations increased. For the first time, PBA@ZnO was used as a turn-off nano-sensor for the spectrofluorimetric measurement of SY. The method’s markable sensitivity was demonstrated within an SY linearity range of 50–500 ng/mL, where the limit of detection was calculated as 9.77 ng/mL. Real sample analysis in the food industry, including samples from real food, soft drinks, and sun cream, was made possible by the detection of tiny amounts of SY. Analytical Greenness (AGREE), AGREEprep, and the complementing Green Analytical Procedure Index (Complex MoGAPI) were used to illustrate the new approach’s exceptional eco-friendliness and greenness. The RGB 12 algorithm worked to demonstrate that the suggested approach is less costly, more environmentally friendly, more sustainable, analytically sound, and whiter than the ones that were previously published. In accordance with ICH principles, the suggested method was validated. This approach offers a promising way to rapidly and accurately identify and measure SY in the food industry, helping to guarantee food safety and maintain the health of customers. Full article

Zinc (Zn)- and copper (Cu)-containing welding fumes elevate inflammatory markers (CRP, TNF-α, IL-6, IL-8) in healthy individuals and welders. Zn- and Cu-containing nanoparticles are toxic to human macrophages. Therefore, ZnO exposure limits are under discussion. In this study, the effects of Zn/Cu-containing welding fume suspensions on A549 alveolar epithelial cells (exposure concentrations: 0.01/0.1/1/10/100 µg/mL) and THP-1 macrophages (additionally 0.001 µg/mL) were investigated over a period of 48 h. Effects on apoptosis, cytotoxicity, genotoxicity, superoxide dismutase (SOD) activity, and cytokine levels (IL-6, IL-8, MIP-1β/CCL4, TNF-α) were evaluated. Welding fume exposure increased SOD activity, and it increased Annexin-V binding and cytotoxicity effects starting at 10 µg/mL in A549 cells and particularly in THP-1 macrophages. A549 cells showed increased IL-6 at 10 and 100 µg/mL, and significant IL-8 release occurred at 10 µg/mL for A549 and 0.1 µg/mL for macrophages. Exposed macrophages released TNF-α at 1 µg/mL after 24 and 48 h and MIP-1β/CCL4 at 0.01 µg/mL after 6 h and at 0.001 µg/mL after 48 h. No genotoxic effects were detected. MIP-1β/CCL4 is a sensitive new biomarker for human macrophages exposed to Zn/Cu-containing welding fumes. The findings suggest that Zn/Cu particles affect lung cells already at doses below current occupational thresholds. Full article

The development of biodegradable alternatives to petroleum-based packaging is essential for environmental sustainability. This study presents a novel approach to enhance the performance of hemicellulose-based films by fabricating xylan/polyvinyl alcohol (PVA) composites reinforced with zinc oxide nanoparticles (nano-ZnO). To address nano-ZnO agglomeration, sodium hexametaphosphate (SHMP) was utilized as a dispersant, while sorbitol improved film flexibility. The composite films were prepared via solution casting, and the effects of nano-ZnO content (0–2.5 wt%) on mechanical, thermal, and barrier properties were systematically evaluated. Results showed that at 2 wt% nano-ZnO loading, the tensile strength increased from 15.0 MPa (control) to 26.15 MPa, representing a 74% enhancement, while oxygen permeability decreased from 1.83 to 0.50 (cm³·μm)/(m²·d·kPa). Additionally, the thermal stability also improved due to hydrogen bonding and uniform nanoparticle dispersion. At this optimized loading, the hydrophobcity was also maximized, with the contact angle peaking at 74.4° and water vapor permeability decreasing by 18% (1.53·10⁻⁶·g·h⁻¹·m⁻¹·Pa⁻¹). Excessive nano-ZnO loading (>2 wt%) induced particle agglomeration, generating stress concentrators that disrupted the polymer–nanoparticle interface and compromised mechanical integrity. These findings highlight the potential of nano-ZnO-modified xylan/PVA films as sustainable, high-performance alternatives to conventional packaging. The synergistic use of SHMP and nano-ZnO provides a strategy for designing eco-friendly materials with tunable properties, advancing the use of biomass in food preservation applications. Full article

Using nanomaterials to replace part of cement is one of the effective ways to enhance the performance of cement-based materials. In this study, the response surface analysis method was used to design an experiment. Through tests on the mechanical properties, the coefficient of water saturation, the shrinkage properties, and the high-temperature calcination of cement-based materials, the effects of three factors, namely, the substitution amount of nano-zinc oxide for cement, the substitution amount of nano-zirconia for cement, and the water–cement ratio, on cement-based materials under different conditions were compared and analyzed. The lower limit of the compressive strength of the cement-based materials increased by 88.17%, and the upper limit increased by 15.14% by using nano-zinc oxide and nano-zirconia to replace part of the cement. The compressive strength of cement-based materials with a nano-zinc oxide content in the range of 0.4–0.6% was low because of the low content of CSH. The coefficient of water saturation decreased with an increase in age, and the coefficient of water saturation of high-performance concrete was low. Nano-zirconia had a significant effect on the mass loss of autogenous shrinkage and the mass loss of drying shrinkage. When the substitution amount of nano-zinc oxide was 0.4–0.8%, the mass loss was large. In summary, with its unique microscopic characteristics, nanomaterials could significantly improve the performance of cement-based materials with regards to their mechanical properties, durability, workability, and other aspects. Full article

The increasing use of nanoparticles (NPs) in various industries has intensified research into plant–NP interactions. NP properties significantly impact their cellular uptake and plant effects, highlighting the need for advanced monitoring techniques to understand their influence on plant growth and seed germination. This study uses biospeckle optical coherence tomography (bOCT) to investigate the size-dependent effects of zinc oxide (ZnO) NPs and microparticles (MPs) on lentil seed internal activity, visualizing dynamic changes under ZnO particle stress. ZnO was selected for its agricultural relevance as a micronutrient. Lentil seeds were submerged in ZnO particle dispersions (<50 nm, <100 nm, 5 μm, 45 μm) at concentrations of 0 (control), 25, 50, 100, and 200 mg/L. OCT structural images were obtained at 12.5 frames per second using a swept-source OCT (central wavelength 1.3 μm, bandwidth 125 nm, sweep frequency 20 kHz). OCT scans were performed before immersion (0 h) and 5, 10, and 20 h after lentil seed exposure to particle dispersion. The biospeckle image, representing dynamic speckle patterns characteristic of biological tissues, was calculated as the ratio of standard deviation to mean of 100 OCT structural images over 8 s. Biospeckle contrast was compared 0, 5, 10, and 20 h post-exposure. ZnO NPs <50 nm and 100 nm negatively impacted lentil seed biospeckle contrast at all concentrations. In contrast, 45 µm ZnO MPs significantly increased it even at 100 mg/L, while 5 μm MPs decreased biospeckle contrast at higher concentrations. bOCT results were compared with conventional morphological (germination percentage, growth, biomass) and biochemical (superoxide dismutase, catalase, and hydrogen peroxide) measurements. Conventional methods require one week, whereas bOCT detects significant changes in only five hours. The results from bOCT were consistent with conventional measurements. Unlike standard OCT, which monitors only structural images, bOCT is capable of monitoring internal structural changes, allowing rapid, non-invasive assessment of nanomaterial effects on plants. Full article

Sizing agents are essential to address the increasing demands of enhanced carbon fibers (CFs), where increasing interfacial adhesion and the analysis of mechanical properties are achieved for critical engineering applications. In this work, five types of self-emulsifying sizing agents, featuring organic polymer–inorganic nano zinc oxide (ZnO) core-shell structures with varying crosslinked polymer densities in the core, were synthesized using self-emulsifying technology through a one-pot, in situ synthetic process. This study revealed that these sizing agents exhibited a uniform particle size distribution within the range of 100–200 nm, along with excellent storage stability and thermal stability up to 300 °C. The optimized sizing agent significantly enhanced the surface properties of CFs, achieving a surface roughness of 6.04 nm and a surface energy of 74.81 mJ/m². Moreover, the interlaminar shear strength (ILSS) and flexural strength of CF/epoxy resin (EP) composites modified with the synthesized sizing agent increased by 86% and 86.43%, respectively, compared to unoptimized composites. These improvements in mechanical properties are attributed to enhanced stress transfer at the CF/EP interface, facilitated by the interlocking mechanism of the nano ZnO particle shell and the superior anti-pressure resistance provided by the crosslinked organic polymer core. Full article

This study presents the fabrication and characterization of highly selective, room-temperature gas sensors based on ternary zinc oxide–molybdenum disulfide–titanium dioxide (ZnO-MoS₂-TiO₂) nanoheterostructures. Integrating two-dimensional (2D) MoS₂ with oxide nano materials synergistically combines their unique properties, significantly enhancing gas sensing performance. Comprehensive structural and chemical analyses, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR), confirmed the successful synthesis and composition of the ternary nanoheterostructures. The sensors demonstrated excellent selectivity in detecting low concentrations of nitrogen dioxide (NO₂) among target gases such as ammonia (NH₃), methane (CH₄), and carbon dioxide (CO₂) at room temperature, achieving up to 58% sensitivity at 4 ppm and 6% at 0.1 ppm for NO₂. The prototypes demonstrated outstanding selectivity and a short response time of approximately 0.51 min. The impact of light-assisted enhancement was examined under 1 mW/cm² weak ultraviolet (UV), blue, yellow, and red light-emitting diode (LED) illuminations, with the blue LED proving to deliver the highest sensor responsiveness. These results position ternary ZnO-MoS₂-TiO₂ nanoheterostructures as highly sensitive and selective room-temperature NO₂ gas sensors that are suitable for applications in environmental monitoring, public health, and industrial processes. Full article