Nanoscale ZnO Research Articles

Anticorrosive and Antibacterial Evaluation of ZnO Nanoscale Sheets Electrosynthesized onto Ti6Al4V and Nitinol Alloys Previously Modified by Chemical Oxidation in H2O2

Anticorrosive and Antibacterial Evaluation of ZnO Nanoscale Sheets Electrosynthesized onto Ti6Al4V and Nitinol Alloys Previously Modified by Chemical Oxidation in H2O2

Zinc oxide nanoparticles cooperate with the phyllosphere to promote grain yield and nutritional quality of rice under heatwave stress

To address rising global food demand, the development of sustainable technologies to increase productivity is urgently needed. This study revealed that foliar application of zinc oxide nanoparticles (ZnO NPs; 30 to 80 nm, 0.67 mg/d per plant, 6 d) to rice leaves under heatwave (HW) stress increased the grain yield and nutritional quality. Compared with the HW control, the HWs+ZnO group presented increases in the grain yield, grain protein content, and amino acid content of 22.1%, 11.8%, and 77.5%, respectively. Nanoscale ZnO aggregated on the leaf surface and interacted with leaf surface molecules. Compared with that at ambient temperature, HW treatment increased the dissolution of ZnO NPs on the leaf surface by 25.9% and facilitated their translocation to mesophyll cells. The Zn in the leaves existed as both ionic Zn and particulate ZnO. Compared with the HW control, foliar application of ZnO NPs under HW conditions increased leaf nutrient levels (Zn, Mn, Cu, Fe, and Mg) by 15.8 to 416.9%, the chlorophyll content by 22.2 to 24.8%, Rubisco enzyme activity by 21.2%, and antioxidant activity by 26.7 to 31.2%. Transcriptomic analyses revealed that ZnO NPs reversed HW-induced transcriptomic dysregulation, thereby enhancing leaf photosynthesis by 74.4%. Additionally, ZnO NPs increased the diversity, stability, and enrichment of beneficial microbial taxa and protected the phyllosphere microbial community from HW damage. This work elucidates how NPs interact with the phyllosphere, highlighting the potential of NPs to promote sustainable agriculture, especially under extreme climate events (e.g., HWs).

Visible light-induced degradation of phenolic contaminants utilizing nanoscale TiO2 and ZnO impregnated with SR 7B (SR) dye as advanced photocatalytic systems

Visible light-induced degradation of phenolic contaminants utilizing nanoscale TiO2 and ZnO impregnated with SR 7B (SR) dye as advanced photocatalytic systems

Comparing the individual and combined effects of nano zinc and conventional zinc fertilization on growth, yield, phytochemical properties, antioxidant activity, and secoisolariciresinol diglucoside content in linseed

Zinc sulfate (ZnSO4), a conventional Zn fertilizer, is widely used due to its high solubility and ease of application. In contrast, nano Zn represents an innovative approach, utilizing nanoscale particles to enhance Zn bioavailability and uptake efficiency. This study compares these two Zn fertilizers regarding their impact on plant growth, yield, Zn uptake, and overall crop quality. In our study, we explored the potential of nano Zn and ZnSO4 by applying two different doses of each (100, 1000 ppm ZnO NP and 30, 50 kg ha−1 ZnSO4) both individually and in combination, to linseed accession. The results obtained showed the potential of nano Zn over conventional Zn fertilizer in terms of enhanced linseed growth and yield together with greater antioxidants enzyme, oil content, protein content, Zn accumulation, secoisolariciresinol diglucoside (SDG) content, and the accumulation of bioactive metabolites. Nanoscale ZnO (with particle size less than 100 nm) at a 1000 ppm concentration sped up growth, yield, increased SDG content, and antioxidant activity. However, when nano Zn (1000 ppm) was applied in combination with ZnSO4 (30 kg ha−1), it maximally enhanced plant fresh and dry weight, photosynthesis, and yield compared to their individual treatment. The combined application increased seed yield by 4.55 folds compared to the control. The treated plants were assessed for SDG content using liquid chromatography-mass spectrometry analysis (LC-MS), which showed maximum increase with 1000 ppm ZnO NP. SDG is a type of lignan known for their antioxidant properties and potential health benefits paving way for its pharmaceutical importance.

Nanoscale ZnO doping in prosthetic polymers mitigate wear particle-induced inflammation and osteolysis through inhibiting macrophage secretory autophagy

Wear particles produced by joint replacements induce inflammatory responses that lead to periprosthetic osteolysis and aseptic loosening. However, the precise mechanisms driving wear particle-induced osteolysis are not fully understood. Recent evidence suggests that autophagy, a cellular degradation process, plays a significant role in this pathology. This study aimed to clarify the role of autophagy in mediating inflammation and osteolysis triggered by wear particles and to evaluate the therapeutic potential of zinc oxide nanoparticles (ZnO NPs).We incorporated ZnO into the prosthetic material itself, ensuring that the wear particles inherently carried ZnO, providing a targeted and sustained intervention. Our findings reveal that polymer wear particles induce excessive autophagic activity, which is closely associated with increased inflammation and osteolysis. We identified secretory autophagy as a key mechanism for IL-1β secretion, exacerbating osteolysis. Both in vitro and in vivo experiments demonstrated that ZnO-doped particles significantly inhibit autophagic overactivation, thereby reducing inflammation and osteolysis.In summary, this study establishes secretory autophagy as a critical mechanism in wear particle-induced osteolysis and highlights the potential of ZnO-doped prosthetic polymers for targeted, sustained mitigation of periprosthetic osteolysis.

Enhancing Secondary Alkaline Battery Performance: Synthesis and Electrochemical Characterization of Zn Anodes, Based on ZnO@C Core‐Shell Nanoparticles

AbstractWhile alkaline Zn batteries, like traditional rechargeable aqueous batteries, boast an advantage in terms of energy density, their progress has been hampered by concerns related to the anode. These concerns include issues like Zn dendrites, self‐corrosion, passivation, shape change, and the hydrogen evolution reaction (HER). To tackle these challenges, we have introduced a nanostructuring approach for the anode, employing carbon‐coated ZnO nanoparticles (ZnO@C) as the active material. In this study, we synthesized ZnO@C nanoparticles in an environmentally sustainable and scalable manner to address passivation and dissolution issues jointly. Nanoscale ZnO particles effectively prevent passivation, while carbon shell slows down the dissolution of zincate. The Zn anode exhibits a significant performance boost when compared to Zn foil and bare ZnO nanoparticles, even when subjected to demanding conditions (without the use of ZnO‐saturated electrolyte). This rechargeable Zn anode marks a significant step toward the realization of practical, high‐energy rechargeable aqueous batteries, such as Zn‐air batteries.

Formation of High Hardness ZnO/Cu Nanocomposite by Thermal Oxidation from Cu-Zn Alloy Strips

Due to their superior thermal, electrical, and mechanical properties, brass and Cu-Zn alloys are widely used in a broad range of applications. In applications requiring greater durability, corrosion resistance, and wear resistance, however, the ZnO/Cu composite is preferable. Typically, ZnO/Cu composites are manufactured through powder metallurgy. In this article, brass strips are thermally oxidized in an oxygen atmosphere to produce ZnO/Cu composite strips. The optimal temperature and oxygen pressure are 600–650 °C and less than one atmosphere, respectively. The homogeneous distribution of nanoscale ZnO clusters in the Cu matrix can be attributed to the diffusion of both Zn and O in the matrix. In addition, the composite is substantially harder than brass, increasing from 70–90 HV to 200–240 HV. Therefore, thermal oxidation has been shown to be a simple and cost-effective process for producing ZnO/Cu composites with high hardness.

Investigation of the influence of nano ZnO particle doping in electrode membrane on the output characteristics of biomimetic artificial muscles

AbstractBiomimetic artificial muscles (BMAMs) aim to imitate the movement and capabilities of natural muscles, drawing inspiration from their structure and function. This research utilized multiwalled carbon nanotubes to increase the conductivity of the electrode membrane and replaced traditional electroactive polymers with sodium alginate to improve the output performance of BMAMs. To further strengthen the output force of the electrode membrane, nanoscale ZnO was chosen as the doping material. Various composite electrode membranes were created during the experiments, each containing varying amounts of ZnO nanoparticles. The membranes' surface morphology was extensively examined with scanning electron microscopy, and the composite electrode membranes were fully assessed on an electrochemical workstation. Electrochemical testing showed that adding nanoscale ZnO particles greatly boosted the specific capacitance of the electrode membrane, which was directly linked to the performance of BMAMs. Impedance spectroscopy test results indicated a minimal impact of nanoscale ZnO particle doping on the internal resistance of the electrode membrane.Highlights Sodium alginate replaces electroactive polymers, easing environmental impact. Nano ZnO doping boosts electrode membrane's capacitance for stronger muscles. ZnO doping shows minimal effect on electrode membrane's resistance.

The influence of zinc oxide-silicate composites on the aging resistance of asphalt

Asphalt binder is susceptible to aging from heat, air and sunlight exposure during service, leading to pavement distresses. This study aimed to improve the aging resistance of asphalt using zinc oxide-silicate (ZOS) composites. ZOS containing 2–8 wt% ZnO were synthesized via a one-step sol-gel method and incorporated into an unmodified 70/100 penetration grade asphalt binder. The rheological properties and aging characteristics were evaluated before and after rolling thin film oven and pressure aging vessel protocols. Dynamic shear rheometry showed increased complex modulus and decreased phase angle for ZOS-modified binders, indicating improved rutting resistance. Aging indices revealed the 6% ZOS composite had the least susceptibility to oxidative aging. FTIR analysis confirmed the formation of carbonyl and sulfoxide functional groups during aging, which were mitigated by ZOS addition. Scanning electron microscopy visualized nano-scaled ZnO particles dispersed within the silica matrix and asphalt binder. The ZOS composites delayed the aging rate through physicochemical interactions between ZnO and the asphalt medium. An optimum ZOS dosage of 4–6% was found to enhance the anti-aging properties. The renewable silica-supported ZnO composites show potential as cost-effective modifiers for improving asphalt durability.

Green fabrication of ZnO nanoparticles via spirulina platensis and its efficiency against biofilm forming pathogens

Excessive consumption of antibiotics is considered one of the top public health threats, this necessitates the development of new compounds that can hamper the spread of infections. A facile green technology for the biosynthesis of Zinc oxide nanoparticles (ZnO NPs) using the methanol extract of Spirulina platensis as a reducing and stabilizing agent has been developed. A bunch of spectroscopic and microscopic investigations confirmed the biogenic generation of nano-scaled ZnO with a mean size of 19.103 ± 5.66 nm. The prepared ZnO NPs were scrutinized for their antibacterial and antibiofilm potentiality, the inhibition zone diameters ranged from 12.57 ± 0.006 mm to 17.33 ± 0.006 mm (at 20 µg/mL) for a variety of Gram-positive and Gram-negative pathogens, also significant eradication of the biofilms formed by Staphylococcus aureus and Klebsiella pneumoniae by 96.7% and 94.8% respectively was detected. The free radical scavenging test showed a promising antioxidant capacity of the biogenic ZnO NPs (IC50=78.35 µg/mL). Furthermore, the anti-inflammatory role detected using the HRBCs-MSM technique revealed an efficient stabilization of red blood cells in a concentration-dependent manner. In addition, the biogenic ZnO NPs have significant anticoagulant and antitumor activities as well as minimal cytotoxicity against Vero cells. Thus, this study offered green ZnO NPs that can act as a secure substitute for synthetic antimicrobials and could be applied in numerous biomedical applications.

Formation of zinc oxide composites of doxycycline with high antibacterial activity based on DC-magnetron deposition of ZnO nanoscale particles on the drug surface

Formation of zinc oxide composites of doxycycline with high antibacterial activity based on DC-magnetron deposition of ZnO nanoscale particles on the drug surface

A cooperative nanoscale ZnO–NiO–Ni heterojunction for sustainable catalytic amidation of aldehydes with secondary amines

Metal–metal hydroxide/oxide interface catalysts are valued for their multiple active sites, enabling synergistic reactions in close proximity for advanced catalytic applications.

Nanoscale ZnO Improves the Amino Acids and Lipids in Tomato Fruits and the Subsequent Assimilation in a Simulated Human Gastrointestinal Tract Model.

With the widespread use of nanoenabled agrochemicals, it is essential to evaluate the food safety of nanomaterials (NMs)-treated vegetable crops in full life cycle studies as well as their potential impacts on human health. Tomato seedlings were foliarly sprayed with 50 mg/L ZnO NMs, including ZnO quantum dots (QDs) and ZnO nanoparticles once per week over 11 weeks. The foliar sprayed ZnO QDs increased fruit dry weight and yield per plant by 39.1% and 24.9, respectively. It also significantly increased the lycopene, amino acids, Zn, B, and Fe in tomato fruits by 40.5%, 15.1%, 44.5%, 76.2%, and 12.8%, respectively. The tomato fruit metabolome of tomatoes showed that ZnO NMs upregulated the biosynthesis of unsaturated fatty acids and sphingolipid metabolism and elevated the levels of linoleic and arachidonic acids. The ZnO NMs-treated tomato fruits were then digested in a human gastrointestinal tract model. The results of essential mineral release suggested that the ZnO QDs treatment increased the bioaccessibility of K, Zn, and Cu by 14.8-35.1% relative to the control. Additionally, both types of ZnO NMs had no negative impact on the α-amylase, pepsin, and trypsin activities. The digested fruit metabolome in the intestinal fluid demonstrated that ZnO NMs did not interfere with the normal process of human digestion. Importantly, ZnO NMs treatments increased the glycerophospholipids, carbohydrates, amino acids, and peptides in the intestinal fluids of tomato fruits. This study suggests that nanoscale Zn can be potentially used to increase the nutritional value of vegetable crops and can be an important tool to sustainably increase food quality and security.

PET Composite Fiber Membranes Modified with Modified Nanoscale ZnO Exhibit Synergistic Antibacterial Effects

PET Composite Fiber Membranes Modified with Modified Nanoscale ZnO Exhibit Synergistic Antibacterial Effects

Low frequency noise in β -Ga2O3 based nanoelectronic devices

In this work, low frequency noise in β-Ga2O3 nanowire-based (NW) electronic devices is analyzed, which exhibits different behaviors as the device size scales down. The noise spectrum for the narrower NW (∼80 nm) is closer to 1/f characteristics, whereas it starts to show evident 1/f2 components as the NW size gets thicker (∼200 nm), giving clear signs of distinctive features for the bunch of traps at the NW interface or in the bulk. Our results show that 1/f noise in these NW electronic devices seems predominantly originated from an aggregated effect of the intricate trap states close to the β-Ga2O3 NW surface or interface with a wide range distribution, while finite groups of active deep traps play a critical role in contributing 1/f2components via generation-recombination or random telegraph signal processes. Notably, as the bias voltage increases, the 1/f2 components in the noise spectra get more overwhelming and would shift toward lower frequencies, suggesting that electric ionization effects would screen the shallow traps close to the surface or interface based on the Poole–Frenkel model. The Hooge's constants extracted from the 1/f noise component for these β-Ga2O3 NW-based devices fall in the range of 0.008–0.019, which are comparable to those of the best reported devices based on other wide bandgap semiconductor with nanoscale structures, including GaN, ZnO, and SnO2. This work may give hints of revealing the sophisticated dynamic behaviors of traps in the surface/volume β-Ga2O3 materials and electronic devices in the nanoscale by low frequency noises.

Effect of Mg doping on dielectric properties of ZnO nanoparticles synthesized by microwave-assisted combustion route

The primary aim of this research work is to study the dielectric properties of nanoscale ZnO and Mg-doped ZnO nanoparticles (NPs). The microwave-assisted combustion technique was used to synthesize ZnO and Mg-doped ZnO NPs (2, 4, and 6 atomic % of Mg). XRD (X-ray diffraction), FTIR (Fourier transform infrared) and SEM (Scanning electron microscope) methods were used to characterize the materials. From the XRD pattern, the phase confirmation and crystallite size of ZnO and Mg-doped ZnO NPs were estimated. The study of dielectric properties such as dielectric loss and permittivity, impedance and AC conductivity were observed in the range of frequency (1–106 Hz). The permittivity of ZnO and 6% Mg-doped ZnO showed an enhanced dielectric property than other doped materials at higher frequency. The additional mobile carriers added to the material as a result of raising the percentage of doping resulted in an increase in the material's dielectric loss. The hopping and tunnelling mechanism, which may be attributed to the migration of electrons into the conductive network formed by the crystallites of 6% Mg-doped ZnO and ZnO NPs, caused progressively increase in the values of AC conductivity of doped nanoparticles as the frequency range was increased. The impedance (real and imaginary) was decreased with increase in the amount of Mg (in terms of atomic %).

Physical Characteristics, Blue-Green Band Emission and Photocatalytic Activity of Au-Decorated ZnO Quantum Dots-Based Thick Films Prepared Using the Doctor Blade Technique.

Nanoscale ZnO is a vital semiconductor material whose versatility can be enhanced by sensitizing it with metals, especially noble metals, such as gold (Au). ZnO quantum dots were prepared via a simple co-precipitation technique using 2-methoxy ethanol as the solvent and KOH as the pH regulator for hydrolysis. The synthesized ZnO quantum dots were deposited onto glass slides using a simple doctor blade technique. Subsequently, the films were decorated with gold nanoparticles of different sizes using a drop-casting method. The resultant films were characterized via various strategies to obtain structural, optical, morphological, and particle size information. The X-ray diffraction (XRD) reveals the formation of the hexagonal crystal structure of ZnO. Upon Au nanoparticles loading, peaks due to gold are also observed. The optical properties study shows a slight change in the band gap due to Au loading. Nanoscale sizes of particles have been confirmed through electron microscope studies. P.L. studies display blue and blue-green band emissions. The significant degradation efficiency of 90.2% methylene blue (M.B.) was attained in natural pH in 120 min using pure ZnO catalyst while one drop gold-loaded catalysts, ZnO: Au 5 nm, ZnO: Au 7 nm, ZnO: Au 10 nm and ZnO: Au 15 nm, delivered M.B. degradation efficiency of 74.5% (in 245 min), 63.8% (240 min), 49.6% (240 min) and 34.0% (170 min) in natural pH, respectively. Such films can be helpful in conventional catalysis, photocatalysis, gas sensing, biosensing, and photoactive applications.

Photocatalytic cyclohexane oxidation and epoxidation using hedgehog particles

Inorganic particles are effective photocatalysts for the liquid-state production of organic precursors and monomers at ambient conditions. However, poor colloidal stability of inorganic micro- and nanoparticles in low-polarity solvents limits their utilization as heterogeneous catalysts and coating them with surfactants drastically reduces their catalytic activity. Here we show that effective photo-oxidation of liquid cyclohexane (CH) is possible using spiky particles from metal oxides with hierarchical structure combining micro- and nanoscale structural features engineered for enhanced dispersibility in CH. Nanoscale ZnO spikes are assembled radially on α-Fe2O3 microcube cores to produce complex ‘hedgehog’ particles (HPs). The ‘halo’ of stiff spikes reduces van der Waals attraction, preventing aggregation of the catalytic particles. Photocatalysis in Pickering emulsions formed by HPs with hydrogen peroxide provides a viable pathway to energy-efficient alkane oxidation in the liquid state. Additionally, HPs enable a direct chemical pathway from alkanes to epoxides at ambient conditions, specifically to cyclohexene oxide, indicating that the structure of HPs has a direct effect on the recombination of ion-radicals during the hydrocarbon oxidation. These findings demonstrate the potential of inorganic photocatalysts with complex architecture for ‘green’ catalysis.

Laser-Patterned Porous Carbon/ZnO Nanostructure Composites for Selective Room-Temperature Sensing of Volatile Organic Compounds

The development of mobile, noninvasive, and portable sensor technologies for diagnostics and emission control is highly demanded. For that purpose, laser carbonization is studied as a tool to produce responsive carbon materials from inexpensive organic precursors for the room-temperature selective detection of volatile organic compounds (VOCs) applicable in future sensor array-based devices. To increase the response of intrinsically low-responsive laser-patterned carbons (LP-C) to analytes in the gas phase, we tested carbonization in the presence of nanoscale ZnO precursors in primary inks. Following the addition of a zinc salt, Zn(NO3)2, a noticeable 43-fold increase in the sensor response (ΔR/R0 = −21.5% toward 2.5% acetone) was achieved. This effect is explained by a significant increase in the measurable surface area up to ∼700 m2·g–1 due to the carbothermic reduction supported by the in situ formation of ZnO nanoparticles. Varying Zn concentrations or the addition of as-prepared ZnO nanorods lead to different surface properties like the surface area, porosity, and polarity of LP-C. A predominant effect of the surface polarity on the selectivity toward different analytes of the sensors during physisorption, e.g., acetone vs toluene, was identified and tested. The best-performing LP-C sensors were finely characterized by transmission/scanning electron microscopies and X-ray photoelectron/energy-dispersive X-ray/Raman spectroscopies.

Manganese-Tunable p-type ZnO Nanoscale for Optimized Photocatalytic Degradation of Terasil Blue from Wastewater

Manganese-Tunable p-type ZnO Nanoscale for Optimized Photocatalytic Degradation of Terasil Blue from Wastewater