Search

CuO ceramics were synthesized using the cold sintering process (CSP). CuO nanoparticles with an average size of ∼115 nm were employed as the starting powders. The CuO ceramic samples were fabricated under a pressure of 400 MPa at temperatures ranging from 150 to 300 °C for 30 min (CSP samples). A relative density greater than 81.9 % was achieved at temperatures ≥200 °C, which was significantly higher than that of samples prepared using the non−cold sintering process (non−CSP). By further annealing the CSP samples at ≥750 °C, the relative density increased to over 90 %. Additionally, the mean grain size of the CSP sample was slightly smaller compared to the non−CSP samples. Remarkably, at a sintering temperature of 200 °C, the CSP sample exhibited a giant dielectric permittivity of 17,000 at 1 kHz and room temperature, whereas the non−CSP samples did not exhibit such high dielectric permittivity. Furthermore, the dielectric permittivity of the CSP sample demonstrated slight frequency dependence across the range of 40–105 Hz. This research introduces a novel method for achieving giant dielectric materials at a low temperature of 200 °C. The dielectric permittivity increased further by annealing at 700–900 °C, which was attributed to the increase in relative density. The giant dielectric properties were explained using X−ray photoelectron spectroscopy, attributing them to charge hopping between Cu+ and Cu2+, the grain boundary barrier layer capacitor, and sample−electrode effects. [ABSTRACT FROM AUTHOR]

Recently, research on photocatalysis has become indispensable in tackling the key global environmental issues caused by rapid urbanization and industrialization. In the present work, novel Sn-doped ZnS@CuO composites were designed for visible light driven wastewater remediation and explored the optimum concentration of CuO with enhanced photocatalytic efficiency. The study aimed to tailor the optical response of the photocatalysts to utilize the visible spectrum with enhanced performance against organic pollutants. For the development of Sn-doped ZnS@CuO composites, CuO flowers were prepared via a simple hydrothermal technique, whereas a chemical co-precipitation procedure was used to create Sn-doped ZnS nanoparticles (NPs). The X-ray diffraction confirmed the monoclinic phase of CuO, whilst ZnS crystallized in a wurtzite structure. The diffraction patterns of the Sn-doped ZnS@CuO composites comprised of Sn-doped ZnS and CuO co-existing phases. The crystallite sizes were determined to be in the range between 8 and 28 nm. Energy dispersive X-ray spectroscopy further confirmed the elemental information of the photocatalysts. The FESEM images demonstrated a flower-like morphology for CuO, while Sn-doped ZnS revealed agglomeration of NPs. Furthermore, the optical response of Sn-doped ZnS@CuO composites was significantly improved towards the visible region with the addition of CuO. Particularly, the Sn-doped ZnS@CuO composites with a 75 % CuO ratio (marked as W1) revealed an outstanding methylene blue (MB) removal efficiency of 96 %. The current work suggests that the novel Sn-doped ZnS@CuO composites can be utilized for the degradation of toxic pollutants from the aquatic environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Copper oxide (CuO) nanostructures have gained popularity in glucose biosensor development due to their excellent electrochemical properties, affordability and ease of fabrication. This review examines the progress of glucose biosensors based on CuO nanostructures and shows differences between enzyme-based and enzyme-dependent systems. Enzyme-based glucose oxidase sensors offer high specificity but are hampered by difficulties associated with enzyme stability at different temperatures, pH and interfering inhibitors. Unlike nonenzyme-based sensors, those using glucose oxidation directly offer high sensitivity and long working life but are struggling with specificity. The main drivers of these sensors are nanostructure morphology, synthesis techniques, surface modifications and electrode materials. The switch from more conventional CuO to sophisticated nanostructures significantly improved the sensitivity and durability of the sensor. This research focuses on optimizing these variables to address existing limitations and to advance CuO nanostructures as leads for next-generation glucose biosensing technologies. [ABSTRACT FROM AUTHOR]

The CuO nanorods were in-situ grown on sensing electrodes by a chemical bath method for the detection of volatile organic compounds (VOCs). The synthesized material was characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR). The CuO nanorods, with lengths of 100–150 nm and diameters of 35–55 nm, were uniformly formed into a thin film on the electrode surface, with a thickness of approximately 1 μm. The gas test results demonstrated that the sensor achieved a peak response of 1.32 for formaldehyde at 200 °C, and a response of 1.92 for ethanol at 175 °C. At a concentration of 50 ppm, ethanol and formaldehyde at an operating temperature of 200 °C exhibit short response/recovery times of 28 s/48 s for ethanol and 45 s/62 s for methanol, respectively, coupled with good reproducibility. Moreover, the sensor exhibited a power-law response to varying gas concentrations and showcased superior selectivity in the VOCs gas detection. This in-situ growing CuO of our work provides a facial gas sensing material fabricated method. [ABSTRACT FROM AUTHOR]

The CuO-mesoporous silicon oxide nanocomposites are widely used in the adsorption and degradation of environmental pollutants, attributing to the effective photogenerated electrons and holes and high specific surface area of mesoporous silicon oxide. In this papers, Cu(NO3)2 was introduced during the assembly process of mesoporous silicon oxide to prepare CuO/MCM-41 nanocomposites by one-step method, which significantly simplified the preparation process compared to post-synthesis transplantation method. The prepared CuO/MCM-41 nanocomposites was characterized by Brunauer–Emmett–Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FE-SEM), Energy-dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). CuO/MCM-41 nanocomposites had excellent degradation effect under UV irradiation of 12W on different structures dyes, such as Methylene Blue(MB), Direct Fast Scarlet 4BS, Direct Yellow 27 and Reactive Turquoise Blue KN-G. It was demonstrated that the kinetic studies of photocatalytic degradation of MB were fitted well with the first-order kinetic model. The degradation of MB retained 97% after five cycles reusing of the catalyst. The results indicated that CuO/MCM-41 nanocomposites could be used as an effective photocatalyst for the degradation of different types of dyes in wastewater. [ABSTRACT FROM AUTHOR]

This work reports a green synthesis of CuO/NiO nanocomposite with different CuO/NiO ratios. The X-ray diffraction (XRD) confirmed the existence of both CuO and NiO. This was also confirmed by energy dispersive X-ray (EDX). Scanning electron microscopy (SEM) reveals that changing the compositions of the nanocomposites resulted in different surface morphologies with different particle shapes, sizes, and levels of aggregation. Nitrogen adsorption-desorption analysis showed microporous structures with pore size in the range of 1.66-1.75 nm and surface area in the range of 82-513 m2g−1. The supercapacitive activity was examined by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). The results display that the 1C3N exhibited the highest capacitive performance of 1072 Fg−1 compared to 760, 716, and 260 Fg−1 for 3C1N, 4 N, and 4 C, respectively. Furthermore, the 1C3N electrode shows a cyclic stability of 72% after 4000 cycles, which makes it a promising candidate for supercapacitive applications. [ABSTRACT FROM AUTHOR]

Developing the sustainable and cost‐effective heterogeneous catalytic system for controlling chemoselectivity holds substantial importance in fine organic chemicals. Herein we construct a unique Zr(OH)4 + CuO physically hybrid system for selective oxidation of anilines. Zr(OH)4 alone leads to azoxybenzene formation, and Zr(OH)4 + CuO shifts the reaction favorably toward nitrosobenzene. The proximity study indicates Zr(OH)4 + CuO outperforms its counterparts synthesized through methods like ball‐milling, loading, and coprecipitation, because the closer proximity exhibits stronger chemical interaction, restricting the activity of Zr‐OH hydroxyl sites. Through mechanistic experiments, in situ DRIFT‐IR and DFT calculations, a new Ph‐N˙OH intermediate mechanism is firstly proposed. Two Ph‐N˙OH self‐condensate to form azoxybenzene for only Zr(OH)4, whereas Zr(OH)4 + CuO could promote rapid transformation of Ph‐N˙OH to nitrosobenzene on CuO through a hydrogen transfer process. Moreover, Zr(OH)4 + CuO displays good recyclability and robust scalability. This is the first report demonstrating the utilization of a physically hybrid catalyst to adjust the selectivity of the aniline oxidation reaction. [ABSTRACT FROM AUTHOR]

Electrochemical carbon dioxide reduction (ECR), which converts carbon dioxide into valuable chemical substances, effectively achieves sustainable carbon neutrality. In this study, we report that CuO catalysts with varying vacancy (CuO-O V) concentrations and morphological structures. CuO-O V can significantly enhance the selectivity for ethylene (C 2 H 4) and multicarbon products (C 2+) by reducing the free energy required for the formation of ∗CHO intermediates from ∗CO hydrogenation and lowering the energy barrier for C-C coupling reactions. The CuO(NaOH) catalyst exhibited a maximum Faradaic efficiency of 55.7% for the C 2+ product at -1.36 V vs. RHE. And C 2 H 4 displays a maximum Faradaic efficiency of ∼32.7% at -1.56 V vs. RHE. • CuO catalysts with different vacancy concentrations and structures can be prepared by adjusting the reaction conditions. • Oxygen vacancies facilitate the conversion of ∗CO intermediates into ∗CHO intermediates through hydrogenation. • Oxygen vacancies facilitate coupling reactions between ∗CO intermediates and ∗CHO intermediates. [ABSTRACT FROM AUTHOR]

Polymethyl methacrylate (PMMA) has garnered significant attention in the field of dentistry due to its wide applications. This paper proposes the incorporation of the nystatin coated copper oxide (CuO) particles having desirable conductivity and antifungal properties, as a filler in the PMMA denture to address their low thermal conductivity, low impact strength, low fatigue resistance, and microbial adhesion. The prepared nystatin coated CuO particles were characterized with several analytical techniques. The nystatin coated CuO particles were mixed in different ratios (0%, 1%, 2%, and 4%) in PMMA corresponding to groups C, E1, E2, and E3, respectively. The prepared samples of composite PMMA with nystatin coated CuO were evaluated to determine their transverse strength, impact strength, Vickers hardness (HV), and thermal conductivity. Furthermore, antifungal properties of CuO particles, nystatin coated CuO particles, and their acrylic composites were evaluated against Candida albicans. Scanning electron microscopy (SEM) analysis confirmed the particles' spherical and irregular shapes. The particle sizes range from nano to micron level. Fourier‐transform infrared spectroscopy (FTIR) and energy dispersive X‐ray spectroscopy (EDX) analysis confirmed the coating of nystatin on CuO. X‐ray diffraction (XRD) analysis showed the diffraction patterns and planes of CuO monoclinic shape structure. The composite prepared to have higher values of HV (19.53 ± 0.65, 20.16 ± 0.37, and 21.11 ± 0.75, respectively) as compared to the control. The impact strength values were measured high at 14.12 ± 5.55 kJ/m2 for 2% containing nystatin coated CuO acrylic resins compared to control and other groups. The conductivity increased linearly with the addition of CuO particles. The addition of CuO particles causes a reduction in flexural strength as compared to the control group. As the concentration of nystatin coated CuO (1%, 2%, and 4%) in acrylic samples increased, the antifungal properties were improved. Thus, the incorporation of optimized concentrations of nystatin coated CuO particles in acrylic resin resulted in the improved mechanical, thermal, and antifungal properties. [ABSTRACT FROM AUTHOR]

The woven carbon fibers (WCF) fabrics were functionalized by growing copper-oxide (CuO) nanostructures using Seed-assisted hydrothermal technique. The effective growth of CuO on surface hydrolyzed WCF samples were achieved by seeding followed by growth treatment in the prepared precursor solution. The impact of hydrothermal process parameters such as number of seeding cycles, duration of growth treatment and molar concentration of growth solution were studied by performing 96 set of experiments with three repetitions. In this work detailed analysis of structural, morphological, and elemental attributes of the CuO-coated WCF fabrics samples have been done. The WCF fabrics were uniformly coated with monoclinic CuO nanostructures having nanopellets, nanoflakes, nanowires, and nanoflowers morphologies. Different characterization techniques such as field emission scanning electron microscope, energy dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, FT-IR spectroscopy and thermo-gravimetric analyzer were used to study different attributes of CuO-modified WCF samples. The number of seeding treatments and the length of growth treatment had a significant impact on growth of CuO nanostructures on WCF. The detailed analysis exhibits that the developed CuO-modified WCF samples may enhance interfacial surface area, bonding capacity and reduce void content by allowing nanostructures to cross-link together and with polymer matrix while fabricating composite materials. [ABSTRACT FROM AUTHOR]

Due to the abundance of active components and low cost, pyrite cinder has great potential as an oxygen carrier in the process of chemical looping combustion (CLC). In order to improve the fuel combustion reactivity, we modified pyrite cinder with copper oxide (CuO). The addition of copper oxide could effectively increase the pore volume and oxygen vacancy concentration of pyrite cinder. The modified pyrite cinder with 20 wt% CuO possessed the highest pore volume (0.3 cm3/g) and oxygen vacancy concentration (55.61%). During the long-term redox cycles, the modified pyrite cinder samples showed higher fuel combustion reactivity than the undoped sample. The results of characterization indicated that the crystalline phases of CuO and CuFe 2 O 4 were formed in the CuO-modified pyrite cinder samples. The active components (Fe 2 O 3 , CuFe 2 O 4 and CuO) in the modified pyrite cinder samples were reduced to Fe 3 O 4 , FeO, CuFeO 2 and Cu during the reduction half cycle. The modified pyrite cinder with 20 wt% CuO possessed the highest CH 4 conversion (nearly 100%) and CO 2 selectivity (nearly 100%) in multiple redox testing. The CH 4 conversion of undoped pyrite cinder was only about 60%. When the content of CuO reached 30 wt%, surface sintering occurred for the modified pyrite cinder, resulting in the decrease of CH 4 conversion and surface area. After continuous redox cycles, the CuO-modified pyrite cinder samples could maintain the original crystal structure. [Display omitted] • Raw pyrite cinder was modified by CuO. • CuO promoted the formation of oxygen vacancies. • Fuel combustion reactivity of CuO-modified pyrite cinder was improved significantly. • CuO enhanced the reduction of iron oxide in pyrite cinder. • The optimum amount of CuO was 20 wt%. [ABSTRACT FROM AUTHOR]

Engine coolant, also called antifreeze, is essential to a vehicle's performance since it controls engine temperature, keeps the cooling system from freezing in cold weather and prevents corrosion. To increase engine cooling efficiency, this study looks into using low-concentration hybrid nanofluids to accelerate heat transfer rates in automobile radiators. To maximise heat dissipation within the radiator system, the project focuses on the synthesis, characterisation and practical applications of these nanofluids. Through an extensive literature review, various nanoparticles, including metallic and oxide-based particles, were evaluated for their compatibility and effectiveness in enhancing heat transfer. The chosen nanoparticles underwent thorough characterisation for size, shape and surface properties to determine their suitability for dispersion in a base coolant. Reduced Graphene is known for its good thermal conductivity, making it an ideal candidate for enhancing cooling rates in various applications hence keeping this in mind, this experiment compares and investigates the heat transfer rate in the radiator of an automobile with a hybrid combination of Reduced Graphene Oxide (RGO) + Copper Oxide (CuO) with ethylene glycol and distilled water, at volume fractions of 0.001%, 0.005% and 0.01%. The results show a notable increase in the efficiency of the radiator both in terms of pressure drop and effectiveness. A maximum of 9.2 and 1.5 times increase in temperature drop is recorded at 0.001%, a maximum of 12.3 and 2.08 times increase in temperature drop is noted at 0.005% and the highest of 17.9 and 3.03 times increase in temperature drop is tabulated at 0.01% volume fraction of copper oxide and 0.01% the volume fraction of RGO hybrid nanofluid. It can safely be concluded that compared to the sixty experiments conducted, the recommended nanofluid among them would be Ethylene Glycol and Distilled Water + 0.01% concentration of RGO and CuO hybrid as they have exhibited higher pressure drop, effectiveness and reduction in temperature. [ABSTRACT FROM AUTHOR]

The use of metal and metal oxide nanoparticles is frequently regarded as a potential solution to the issue of bacterial antibiotic resistance. Among the proposed range of nanoparticles with antibacterial properties, copper oxide nanoparticles are of particular interest. Although the antibacterial properties of copper have been known for a considerable period of time, studies on the effects of copper oxide nanomaterials with respect to biological systems have attracted considerable attention in recent years. This review presents a summary of the antibacterial properties of copper oxide nanoparticles, the mechanisms by which the antibacterial effect is realized, and the key reported methods of modifying these nanoparticles to improve their antibacterial activity. A comparative analysis of the effectiveness of these nanoparticles is presented depending on the type of microorganism, the shape of the nanoparticles, and the Gram classification of bacteria based on data from published sources. In addition, the review addresses the biological activities of copper oxide nanoparticles, including their antifungal and cytotoxic properties, as well as their "antioxidant" activity. According to the conducted analysis of the literature data, it can be concluded that copper oxide nanoparticles have a significant bacteriostatic potential with respect to a wide range of microorganisms and, in some cases, contribute to the inhibition of fungal growth. At the same time, the sensitivity of Gram-positive bacteria to the effect of copper oxide nanoparticles was often higher than that of Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

In the present study, polyvinylchloride (PVC) and polymethyl methacrylate (PMMA) blended nanocomposites comprised of graphene nanoplatelets (GNPs), montmorillonite (MMT), and copper oxide (CuO) nanoparticles were prepared through solvent casting approach. The structural and morphological measurements confirmed the presence and dispersion of nanofillers in the polymeric chains. Thermo-gravimetric analysis (TGA) and differential-scanning calorimetry (DSC) investigations suggested the improved thermal stability for nanocomposite with 1.5 wt% GNPs loading having minimum weight loss and reduction in Tm due to the presence of GNPs, MMT, and CuO acting as a barrier to oxygen molecule diffusion and polymer-chain movement in the nanocomposite. The dielectric and impedance properties of PVC/PMMA/MMT/GNP/CuO nanocomposite investigated in 1 Hz to 20 MHz frequency range and at room temperature have shown improved dielectric constant upto 90.59 in 1 Hz frequency. The σac measures to be improved by 0.0034 (S/m) after adding GNPs, MMT, and CuO resulted from the interfacial polarization effect. The cole–cole plot investigations have shown the formation of semicircles for higher nanofiller loadings of nanocomposite. A drastic improvement in the SETotal was observed from lower to higher nanofiller concentrations. The total SE obtained for the nanocomposite with 2.5 wt% GNPs is upto 5 dB in 8–12 GHz range with absorption dominant nature of nanocomposite. [ABSTRACT FROM AUTHOR]

High-ferrite cement (HFC) has attracted widespread attention due to its advantages, such as low sintering temperature and excellent corrosion resistance. The application of Cu-containing waste in HFC will promote the cement industry toward low-carbon and sustainable development. However, massive amounts of CuO can cause a delay in HFC hydration. The main aim of this paper was to investigate the retardation mechanism of CuO on the hydration of HFC using X-ray diffraction, mercury intrusion porosimetry, isothermal heat-conduction calorimetry, scanning electron microscopy, inductively coupled plasma-optical emission spectroscopy, thermogravimetric analysis and derivative thermogravimetry, among others. The results showed that compared with the undoped clinker, the maximum heat release peak of the clinker doped with 1.5% by weight of CuO was delayed for about 60 h, the hydration induction period was extended from 37 to 89 h, and the compressive strength was zero at 3 days. Through the study of cement suspension at 3 days, it was found that the retardation mechanism is mainly due to the obstruction of Ca leaching. On one hand, the C3S content in the HFC clinker decreases and the grain size of the calcium silicate minerals increases, on the other hand, the Ca2(OH)4·4Cu(OH)2·H2O coats clinker particles at the early stage, leading to a lower hydration degree of the HFC clinker. [ABSTRACT FROM AUTHOR]

Hydrogen and renewable fuels were generated using cost‐effective and efficient electrocatalysts for water splitting. In this work, a CuO‐based photocathode is used for the water splitting to generate hydrogen energy by PVD technique. The XRD analysis reveals the deposition of CuO thin film on ITO substrates, which is monoclinic. The XRD and LSV analysis of CuO confirmed the type of semiconductor and observed to be P‐type semiconductor. SEM study of CuO confirmed the shape, morphology to be a circular and regular shape. The grain size of deposited CuO thin film was found to be 18 nm. The absorption and transmission of CuO thin film were observed through UV spectroscopy analysis and were found to be better photocatalyst in visible range 415–425 nm. The transmittance of the prepared thin film was noted to be maximum 7.6% in the UV range (280–300 nm). The band gap was also measured employing the Tauc plot and found to be 2.98 eV, which is most favorable for water splitting application. FTIR study showed the stretching, vibration, and the functional group of the deposited CuO thin film; the broad band of stretching of Cu‐O in monoclinic CuO was observed at the range of 500–700 cm−1, and further peaks were also noted at the range of 1500–1600 cm−1. The linear sweep voltammetry (LSV) of CuO thin film was calculated in the absence of solar spectra and the presence of solar spectra and observed to be enhanced in current under solar spectra. The solar light to hydrogen emission percentage (STH %) of CuO through LSV was observed to be 2.04% under solar spectra. The low Nyquist curve of blank ITO and CuO‐coated ITO substrate via electrochemical impedance spectroscopy (EIS) analysis was observed, which confirmed the enhancement of EIS of CuO‐coated ITO. The hydrogen generation rate was also calculated by electrochemical cell and observed to be 5325.21 mol g−1 for 6 h. [ABSTRACT FROM AUTHOR]

Background: Green synthesized nanoparticles (NPs) have gained increasing popularity in recent times due to their broad spectrum of antimicrobial properties. This study aimed to develop a phytofabrication approach for producing cuprous (Cu2O) and cupric oxide (CuO) NPs using a simple, non-hazardous process and to examine their antimicrobial properties. Methods: The synthesis employed Bidens pilosa plant extract as a natural reducing and stabilizing agent, alongside copper chloride dihydrate as the precursor. The biosynthesized NPs were characterized through various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Results: XRD analysis confirmed that the synthesized CuO and Cu2O NPs exhibited a high degree of crystallinity, with crystal structures corresponding to monoclinic and face-centered cubic systems. SEM images revealed that the NPs displayed distinct spherical and sponge-like morphologies. EDS analysis further validated the purity of the synthesized CuO NPs. The antimicrobial activity of the CuO and Cu2O NPs was tested against various pathogenic bacterial strains, including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Bacillus cereus, with the minimum inhibitory concentration (MIC) used to gauge their effectiveness. Conclusions: The results showed that the phytosynthesized NPs had promising antibacterial properties, particularly the Cu2O NPs, which, with a larger crystal size of 68.19 nm, demonstrated significant inhibitory effects across all tested bacterial species. These findings suggest the potential of CuO and Cu2O NPs as effective antimicrobial agents produced via green synthesis. [ABSTRACT FROM AUTHOR]

This study examines the impact of copper oxide (CuO), iron oxide (Fe3O4), and their composite (Fe3O4@CuO) nanoparticles on harmful microorganisms in tomato plant roots and stems. The research evaluates agro-environmental factors, including soil composition, moisture levels, and temperature, that influence the efficacy of these nanoparticles. The nanoparticles prepared by the PLAL technique were subjected to structural, morphological, topographic, and optical analysis using a range of methods, including XRD, FE-SEM, EDS, AFM, and UV–Visible spectroscopy. The copper and iron composite particles were found to be polycrystalline, with the iron element present in magnetite and hematite phases. The particles exhibited a spherical form, however, there was agglomeration between them. The optical characteristics exhibited plasmon resonance peaks, indicating the transition of the materials into an optimal nanoscale phase. Both laboratory and field studies were conducted to assess their antifungal activity. The findings reveal that the Fe3O4@CuO composite exhibited superior pathogen suppression compared to the individual nanoparticles. This research offers valuable insights into the application of nanoparticles for controlling plant fungal and bacterial diseases, contributing to more effective and sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Photocatalytic CO 2 reduction presents a promising strategy to alleviate environmental issues caused by massive CO 2 emissions. SrTiO 3 , a potential photocatalyst for photocatalytic CO 2 reactions, is limited by poor photoresponsivity and fast photogenerated carrier recombination. In this work, a series of Cu2+ species modified SrTiO 3 nanofibers (xCuO/STO) was prepared combining sol-gel method and electrospinning with different copper content. The CH 3 OH yield of the 0.08CuO/STO photocatalyst reached up to 5.75 ± 0.27 μmol g−1 h−1, which was 2.2 times higher than that of pure SrTiO 3. It was attributed that the blend electrospinning promoted Cu2+ species to be well dispersed on the surface of the SrTiO 3 nanofibers. The strategy effectively enhanced the light absorption of the photocatalyst and inhibited the recombination of the photogenerated carriers. Part of appropriate characterizations were employed to elucidate the above point. In addition, to explore the inherent mechanism between the two species, the Density Functional Theory (DFT) calculations were further applied in the inherent mechanism between the species. This work provided a blend electrospinning approach for designing cocatalyst-modified SrTiO 3 nanofibers for photocatalytic reduction of CO 2. [Display omitted] [ABSTRACT FROM AUTHOR]

Process intensification engineering of electrocatalysts is crucial to facilitate electrocatalytic reaction, while its cross‐scale modulation is of great challenge. Herein, the spindle CuO supported tungsten single‐atom catalysts (W SACs) with tunable mesoscale electric field and atomic‐scale coordination structure are reported toward enhanced electrochemical hydrogen evolution process. Finite element analysis indicates the mesoscale electric field can be enhanced by tailoring the tip angle of spindle configuration from 74° to 27°, enhancing hydrogen production rate by 5 times. Based on the density functional theory calculations, the configuration regulation also triggers the increase of coordination number of W–O, which increases charge transfer and downshifts d‐band center, stabilizing W sites and optimizing hydrogen desorption process. The optimized WSA/CuO‐27 exhibits much better hydrogen evolution activity (η100 = 94 mV) and stability (200 mA cm−2 for 120 h) than as‐prepared WSA/CuO‐56 and WSA/CuO‐74 analogues. Impressively, the anion exchange membrane electrolyzer fabricated with the WSA/CuO‐27 presents excellent activity comparable to that of commercial electrocatalysts, and also delivers an ultra‐low attenuation of 0.085 mA cm−2 h−1 at 300 mA cm−2 after continuous electrocatalysis for 120 h. This work inspires the design of high‐efficiency supported metal catalysts for electrochemical synthesis via the cross‐scale process intensification engineering. [ABSTRACT FROM AUTHOR]

A composite film of TiO2–CuO synthesized by spray pyrolysis is deposited onto a silicon (Si) substrate and subjected to comprehensive characterization using diverse analytical techniques. X-ray diffraction (XRD) revealed the presence of an anatase phase of TiO2 and a monoclinic phase of CuO, with the highest diffraction occurring on the (101) plane. Raman spectra also depict anatase phase of TiO2. The scanning electron microscope (SEM) image reveals a porous and rough morphology whereas EDX depicts the inclusion of CuO. While UV–Visible diffused reflectance indicates a direct band gap of 3.21 eV. Similarly, photoluminescence (PL) studies reveal a significant reduction in intensity within the UV and blue regions as compared to the yellow region. Likewise, the ideality factor (n) and barrier height (Φb), which are diode parameters are computed based on the I–V characteristics. These findings suggest that the TiO2–CuO film holds potential for applications in the manufacturing of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Simple Summary: Nanoparticles (NPs) have received significant consideration because of their special properties and valuable applications in numerous segments. In the current era, the fast growth of NP manufacturing and their plentiful uses puts the environment at additional risks. To explicate the noxious effects of NPs, numerous plant bioassays have been proposed. Since Pisum sativum L. has complex mitotic dynamics, it is a test plant used to assess the genotoxic effects of environmental pollutants. Using the Pisum sativum test system, this work was designed to assess the toxicity potential of CuO NPs by morphological (SG and RL) and genotoxic (CD, MI, CKP, MNF, and CAF) methods. Even though cytogenetic analyses of environmental pollutants in plants have been reported previously, this is the first work of its type to demonstrate the morphological and genotoxic effects of CuO NPs in Pisum sativum. These studies are very essential, since the pea is a vital food grain crop and a tremendous source of ayurvedic medications and manure, as well as its use as a vegetable. The speedy growth of copper oxide nanoparticle (CuO NP) manufacturing due to their wide application in industries has caused concerns due to their increased discharge into the environment from both purposeful and accidental sources. Their presence at an elevated concentration in the environment can cause potential hazards to the plant kingdom, specifically to staple food crops. However, limited research is available to determine the consequences of CuO NPs. The present study aimed to assess the morphological and cytological changes induced by CuO NPs on Pisum sativum L., a key staple food crop. Seeds of Pisum sativum were exposed to various concentrations of CuO NPs (0, 25, 50, 75, 100, and 125 ppm) for 2 h, and their effects on seed germination (SG), radicle length (RL), cell proliferation kinetics (CPK), mitotic index (MI), cell death (CD), micronucleus frequency (MNF), and chromosomal aberration frequency (CAF) were studied. The results indicate a significant reduction in SG, RL, CPK, and MI and a significant dose-dependent increase in CD, MNF, and CAF. CuO NP treatment has led to abnormal meiotic cell division, increased incidence of micronucleus frequency, and chromosomal aberration frequency. Additionally, the CuO NP-treated groups showed an increase in the percentage of aberrant meiotic cells such as laggard (LG), double bridge (DB), stickiness (STC), clumped nuclei (CNi), precocious separation (PS), single bridge (SB), and secondary association (SA). CuO NP treatment led to reductions in SG as follows: 55% at 24 h, 60.10% at 48 h, and 65% at 72 h; reductions in RL as follows: 0.55 ± 0.021 cm at 24 h, 0.67 ± 0.01 cm at 48 h, and 0.99 ± 0.02 cm at 72 h; reductions in CPK as follows: 34.98% at prophase, 7.90% at metaphase, 3.5% at anaphase, and 0.97% at telophase. It also led to a 57.45% increase in CD, a 39.87% reduction in MI, and a 60.77% increase in MNF at a higher concentration of 125 ppm. The findings of this study clearly show that CuO NPs have a genotoxic effect on the food crop plant Pisum sativum. [ABSTRACT FROM AUTHOR]

The research aims to characterize a melt-quenched sodium silicate glass doped with different concentrations of copper oxide (CuO) as an optical filter material. Sodium oxide (Na2O) was fixed at 45 mol%, whereas CuO was introduced to the glass network at the expense of Na2O, from 0.2 to 0.8 mol%. The silicate network comprises Si–O–Si vibrations in symmetrical and assymmetrical modes, with the formation of non-bridging oxygens (NBOs) as a result of the presence of the modifiers NaO6 and distorted tetragonal CuO6 units. The optical transmittance was zero in the UV region and in the visible region starting from 600–900 nm, depending on the glass composition and the CuO ratio. The glass containing 0.6 mol% CuO had a maximum transmittance peak (T = 0.64) at 450 nm, whereas the glass containing 0.8 mol% CuO exhibited a low transmittance peak (T = 0.28) at 450 nm. The optical parameters were discussed in terms of the effect of CuO, in which the optical band gap varied from 3.168 eV to 2.819 eV as the CuO changed from 0 to 0.8 mol%. Other important parameters like Urbach energy, refractive index, and their related variables were determined and discussed. The glass density of sodium silicate glass is 2.478 g/cm3, which has been slightly increased to 2.491 g/cm3 due to the effect of the CuO dopant. Furthermore, as the CuO content increased, the optical basicity increased from 1.222 to 1.237, indicating that the glass was thermodynamically stable. [ABSTRACT FROM AUTHOR]

The xCuO-(22.2-x)MgO-22.2Al2O3 -55. 6SiO2 (x = 0, 0. 25, 0. 50, 0. 75 and 1. 00, molar fraction) (MAS) glass-ceramics were synthesized using sintering-crystallization method. The effect of CuO content on the crystallization behavior, crystal type, micromorphology and microwave dielectric properties of MAS glass-ceramics was studied. The results show that as the CuO content increases from 0% to 1. 00%, substituting for MgO, the glass transition temperature decreases. Additionally, the precipitation peak temperatures also show a decreasing trend, while the Avrami index n gradually increases. The primary crystalline phase in glass-ceramics is α-cordierite. The inclusion of CuO facilitates the transformation of μ-cordierite to α-cordierite at lower temperatures and reduces the thermal expansion coefficient. With the increase of CuO content, the dielectric constant of glass-ceramics increases first and then decreases, while the dielectric loss decreases first and then increases. At a heat treatment 650 °C / 2 h + 1 050 °C / 2 h, the glass-ceramics doped with 0. 25% and 0. 50% CuO exhibits optimal integrated dielectric properties, which dielectric constant is 5. 04 and 5. 07, dielectric loss is 7. 49 x 10-4 and 7. 12 x 10-4, and quality factor is 20 013. 35 and 20 786. 41 GHz within the frequency range of 14. 6 - 15. 2 GHz. [ABSTRACT FROM AUTHOR]

ASCOT (an acronym derived from Ag-Silver, Copper Oxide, Titanium Oxide) is a user-friendly web tool for digital construction of electrically neutral, energy-minimized spherical nanoparticles (NPs) of Ag, CuO, and TiO2 (both Anatase and Rutile forms) in vacuum, integrated into the Enalos Cloud Platform (https://www.enaloscloud.novamechanics.com/sabydoma/ascot/). ASCOT calculates critical atomistic descriptors such as average potential energy per atom, average coordination number, common neighbour parameter (used for structural classification in simulations of crystalline phases), and hexatic order parameter (which measures how closely the local environment around a particle resembles perfect hexatic symmetry) for both core (over 4 Å from the surface) and shell (within 4 Å of the surface) regions of the NPs. These atomistic descriptors assist in predicting the most stable NP size based on lowest per atom energy and serve as inputs for developing machine learning models to predict the toxicity of these nanomaterials. ASCOT's automated backend requires minimal user input in order to construct the digital NPs: inputs needed are the material type (Ag, CuO, TiO2-Anatase, TiO2-Rutile), target diameter, a Force-Field from a pre-validated list, and the energy minimization parameters, with the tool providing a set of default values for novice users.

Abstract This study presents a simple, sustainable, eco-friendly approach for synthesizing copper oxide (CuO) nanoparticles using Citrus aurantium peel extract as a natural reducing and stabilizing agent. The synthesized CuO and CuO-OP were characterized using various techniques, including surface area measurement (SBET), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), and high resolution transmission electron microscope (HRTEM). DRS analysis determines band gap energy (Eg) of 1.7 eV for CuO and 1.6 eV for CuO-OP. FTIR confirmed the presence of Cu–O bond groups. The XRD and HRTEM results revealed monoclinic and spherical nanostructures, with average particle sizes ranging from 53.25 to 68.02 nm, as determined via Scherer’s equation. EDX analysis indicated incorporation of carbon (1.6%) and nitrogen (0.3%) from the peel extract. The synthesized CuO and CuO-OP NPs exhibited excellent photocatalytic efficiencies for methylene blue dye under UV irradiation, reaching 95.34 and 97.5%, respectively, under optimal conditions; the initial dye concentration was 100 mg/L, the pH was 10, the catalyst dosage was 1 g/L, and the contact time was 120 min. Isothermal studies showed that the adsorption of MB onto the nanoparticles followed the Freundlich isotherm model (R2 = 0.97 and 0.96). Kinetic studies indicated that the degradation followed pseudo-first-order kinetics, with rate constants (K1) of 0.0255 min−1 for CuO and 0.033 min−1 for CuO-OP. The sorption capacities were calculated as 98.19 mg/g for CuO and 123.1 mg/g for CuO-OP. The energy values obtained from the Dubinin–Radushkevich isotherm were 707.11 and 912.87 KJ mol−1, suggesting that chemisorption was the dominant mechanism.

This work reports a green synthesis of CuO/NiO nanocomposite with different CuO/NiO ratios. The X-ray diffraction (XRD) confirmed the existence of both CuO and NiO. This was also confirmed by energy dispersive X-ray (EDX). Scanning electron microscopy (SEM) reveals that changing the compositions of the nanocomposites resulted in different surface morphologies with different particle shapes, sizes, and levels of aggregation. Nitrogen adsorption-desorption analysis showed microporous structures with pore size in the range of 1.66-1.75 nm and surface area in the range of 82-513 m2g−1. The supercapacitive activity was examined by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). The results display that the 1C3N exhibited the highest capacitive performance of 1072 Fg−1 compared to 760, 716, and 260 Fg−1 for 3C1N, 4 N, and 4 C, respectively. Furthermore, the 1C3N electrode shows a cyclic stability of 72% after 4000 cycles, which makes it a promising candidate for supercapacitive applications.

Copper oxide nanoparticles incorporated-zeolite supported-graphitic carbon nitride (CuO/g–C3N4/Zeolite Y) catalyst was fabricated through a facile hydrothermal method, in which CuO nanoparticles were produced via precipitation. The synthesized CuO/g–C3N4/Zeolite Y was examined using characterization techniques such as FT-IR, XRD, XPS, TEM, SEM, EDX, TG, BET, DRS, and PL. BET analysis revealed that integrating zeolite and CuO has increased the surface area of graphitic carbon nitride. Increased separation efficiency and reduced recombination rates of photogenerated electrons and holes in CuO/g–C3N4/Zeolite Y were confirmed by photoluminescence studies. The CuO/g–C3N4/Zeolite Y catalyst exhibits enhanced efficiency for degrading MB and CV dyes compared to pristine g-C3N4 under sunlight exposure. The active species studies demonstrated that hydroxyl radicals, superoxide anion radicals and holes involve in the photocatalytic destruction of pollutants. Additionally, the CuO/g–C3N4/Zeolite Y composite efficiently degraded the antibiotic ceftazidime. Intermediates generated during the degradation process were identified, and plausible degradation pathways for ceftazidime were proposed through LC–MS analysis. This study implies that the synthesized catalyst can be used in the wastewater cleanup process to eliminate persistent organic contaminants and pharmaceutical pollutants under sunlight irradiation. [ABSTRACT FROM AUTHOR]

This study delves into the synthesis and characterization of cellulose nanofibers (NFCs) and their nanobiocomposites incorporating coinage nanoparticles ( Ag,ZnO, and CuO ). NFCs were derived from oil palm empty fruit bunches, yielding fibers with diameters below 5 nm. Silver nanoparticles were synthesized using a reduction method, resulting in spherical particles sized between 10-25 nm. The integration of these nanoparticles into the NFCs matrix was confirmed through SEM, TEM, FT-IR, and XRD analyses. FT-IR spectrum of cellulose nanofibers exhibited peaks at 3399 − 3164 cm^−1 for hydroxyl groups, 2925 − 2812 cm^−1 for the cellulose skeleton, and 1013 cm^−1 for the -C-O-C/-C-O-H group. Significant changes were observed in the spectrum post-nanoparticle addition, notably at 1412 and 1317 cm^−1. SEM analysis revealed microdomains of metallic nanoparticles dispersed within the cellulose nanofiber matrix, contributing to increased molecular orientation and crystallinity index. The crystallinity index of cellulose nanofiber films varied: NFC alone exhibited 76.27%, NFC − ZnO 78.54%, NFC-CuO 77.34%, NFC-Ag 76.29%, and NFC-All 77.95%. These variations directly impacted the mechanical properties of the nanobiocomposites, which exhibited significant improvements. Biological analysis confirmed antimicrobial efficacy against E. coli, S. aureus, and C. albicans due to the presence of metallic nanoparticles. Furthermore, water vapor permeability assessments concluded that the nanobiocomposites are suitable for food packaging applications. These findings underscore the promise of NFC-based nanobiocomposites with coinage nanoparticles for advanced packaging materials. Future research avenues should focus on optimizing nanoparticle loading, refining dispersion techniques, and exploring further applications for these versatile nanobiocomposites.

In this paper, novel application possibilities of CuO nanoparticles were investigated in SAC0307 solder alloy for composite soldering purposes. CuO nanoparticles in 0.25 and 0.5 wt% were mixed into the solder paste to produce composite solder joints. Solder joints were manufactured using standard surface mounting technology from different solder pastes. The solder joints were loaded in an 85 °C/85RH% temperature and humidity test for 4000 h. It was found that the CuO composite solder joints showed improved mechanical quality due to the microstructural refinement, which was studied using scanning electron microscopy (SEM) and focused ion beam (FIB) analysis. On the other hand, the corrosion resistance of CuO joints decreased, as they suffered localized corrosion extensively, which produced longer and more Sn whiskers on their surface than on the reference SAC0307. Density functional theory (DFT) calculations proved that CuO can bond to Sn, but CuO is not chemically inert in the solder bulk. CuO can start a cyclic reaction with the dispersed Cu6Sn5 intermetallics, which produces SnO2 in the solder bulk, ultimately enhancing corrosion. Therefore, CuO nanoparticles are suggested to be applied only in non-corrosive environments, such as space applications.

Abstract This work has applied metal–organic frameworks (MOFs) with high adsorbability and catalytic activity to develop electrochemical sensors to determine free chlorine (free-Cl) concentrations in aqueous media. A zeolitic imidazolate frameworks, Zn(Hmim)2 (ZIF-8) has been synthesized and incorporated with CuO nanosheets to decorate a glassy carbon electrode (GCE) and provide a new sensor for free-Cl determination. The as-prepared ZIF-8 and CuO-ZIF-8 composites have been characterized by FESEM, EDX, XRD, and FT-IR analyses. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) utilized to characterize the CuO-ZIF-8/GC modified electrode electrochemically, demonstrated the ability of the sensor to measure free-Cl concentration. Using differential pulse voltammetry (DPV) and under the optimal conditions, the prepared CuO-ZIF-8/GC modified electrode showed a linear response in the 0.25–60 ppm range with a 12 ppb detection limit (LOD) for free-Cl concentration. Finally, the fabricated sensor was applied to analyze free-Cl from actual swimming pool water samples with promising 97.5 to 103.0% recoveries.

This research study investigates how incorporating soft nanoparticles affect the wear behavior and the characteristics of the materials in three-body mixed lubrication conditions. A disk-on-block tribometer was used to revealed a positive correlation between plasticity index and wear rates, indicating that increased plastic deformation leads to higher wear. The size and concentration of copper oxide (CuO) nanoparticles significantly influenced wear behavior. The study found that for block materials with a hardness of 27 HRC and 43 HRC paired with a disk of 58 HRC, increasing nanoparticle concentration and using larger nanoparticles relative to surface roughness (larger nanoparticle size and surface roughness ratio) resulted in reduced wear. The larger nanoparticles can more effectively fill the gaps on the smoother surface, increasing contact area and minimizing plastic deformation during sliding, especially when the contact is more elastic. However, when the counteracting block material is significantly harder than the disk, the effect of nanoparticles might be reversed, potentially leading to increased wear. These findings suggest a complex interplay between material properties, nanoparticle characteristics, and wear resistance, influenced by the relative hardness of contacting surfaces. This research offers valuable insight for developing materials with improved wear performance in applications involving sliding friction in third-body contact.

The surface metallization of Si 3 N 4 ceramics with the Ag–Cu conductive paste containing CuO was systematically investigated. The interfacial reactions between CuO and Si 3 N 4 promoted the surface metallization of the ceramic substrate in an argon atmosphere. The effects of Ag and Cu relative contents on the evolution of the thick film surface morphology were studied. The electrical properties and tensile strength of composite ceramic substrates were enhanced through the generation of Ag–Cu eutectic solution within the thick film layer. The effect of brazing time on the properties of Ag–Cu/Si 3 N 4 composite ceramic substrates was investigated. Mechanical testing and scanning electron microscopy (SEM) were used to analyze the interface tensile strength of the Ag–Cu/Si 3 N 4 composite substrates and the morphology of the Ag–Cu film, and the bonding mechanism of the composite ceramic substrate was studied. When the sample was brazed at 800 °C for 20 min, the maximum tensile strength of 23.6 MPa between the Ag–Cu film and ceramic substrate was obtained, the lowest resistivity of 6.22 μΩ•cm was obtained. The bonding interface between thick film layer and the ceramic substrate formed the Ag–Cu mechanical structure was benefit for improving the comprehensive performance of the Cu/Si 3 N 4 composite ceramic substrate. [ABSTRACT FROM AUTHOR]

An effective approach to enhance the photocatalytic performance of CuO nanoparticles (NPs) is the use of hydrothermal synthesis. The CuO NPs were synthesized by hydrothermal technique in the presence of anionic surfactant. Structural, functional, morphological, chemical composition and optical properties of the synthesized NPs were characterized by using XRD, FTIR, SEM, UV-visible DRS and PL. The average crystallite size for pure, 0.05 M SHMP and 0.05 M SHMP assisted CuO samples are around 13 nm, 11 nm and 10 nm respectively. It was observed that the size of particle is affected by the nature of surfactant. Additionally, in all the samples, FTIR spectra show three identical Cu-O vibration modes that indicate the presence of crystalline CuO monoclinic structure. Thus, the spherical like CuO nanostructure can be used as an ideal material for photocatalytic performance. The synthesized NPs are then used to photo-catalytically degrade the methyl violet dye in aqueous media. Surfactant-assisted CuO NPs showed better photocatalytical activity than bare CuO NPs. [ABSTRACT FROM AUTHOR]

Transition metal oxides are considered to be highly promising anode materials for high-energy lithium-ion batteries. While carbon matrices have demonstrated effectiveness in enhancing the electrical conductivity and accommodating the volume expansion of transition metal oxide-based anode materials in lithium-ion batteries (LIBs), achieving an optimized utilization ratio remains a challenging obstacle. In this investigation, we have devised a straightforward synthesis approach to fabricate CuO nano powder integrated with carbon matrix. We found that with the use of a sodium carboxymethyl cellulose (CMC) based binder and fluoroethylene carbonate additives, this anode exhibits enhanced performance compared to acrylonitrile multi-copolymer binder (LA133) based electrodes. CuO@CMC electrodes reveal a notable capacity ~1100 mA h g−1 at 100 mA g−1 following 170 cycles, and exhibit prolonged cycling stability, with a capacity of 450 mA h g−1 at current density 300 mA g−1 over 500 cycles. Furthermore, they demonstrated outstanding rate performance and reduced charge transfer resistance. This study offers a viable approach for fabricating electrode materials for next-generation, high energy storage devices. [ABSTRACT FROM AUTHOR]

The presence of oil-contaminated water due to oil spill disasters or improper industrial waste dumping is now a worldwide danger to both human health and the sustainability of the environment.The use of superhydrophobic materials has attracted considerable attention in the field of oil-water separation, owing to the increasing demand for effective and economical oil-water separation techniques.A new, easy, and inexpensive flame treatment method was used to make a nanocomposite (CuO-SiO2) in order to improve its hierarchical structure (micro-nano).The anodisation process produced copper oxide (CuO) nanostructures (NSs) on a copper mesh. Subsequently, the nanostructures were modified by dip coating with a solution of room-temperature vulcanised silicone rubber (RTV-SR).The coated mesh demonstrated remarkable characteristics of superhydrophobicity and superoleophilicity, with a water contact angle (WCA) of (160 ± 1°) and an oil contact angle (OCA) of (0°), as determined during the measurement of the surface's wetability. The coated mesh surface was characterised using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS).The successful separation of kerosene-water and diesel oil-water mixtures is accomplished by using a coated mesh in a simple filtration procedure. Furthermore, it has the capability to separate oils with a high efficiency of (99.8%) for kerosene and (87%) for diesel oil. It also has flux values of (7352.9 L.m-2.h-1) for kerosene and (6112.9 L/m2.h) for diesel. [ABSTRACT FROM AUTHOR]

Designing scaffolds to fit with essential requirements for wound dressings is still a challenge. A material with high antibacterial activity and biocompatibility is targeted. In this case, the electrospinning technique is used to fabricate a nanofiber scaffold of polylactic acid (PLA) embedded with ginger and/or molybdenum trioxide (MoO3) and cupric oxide (CuO). The nanofiber scaffolds were examined using SEM, TEM, Raman, XRD, FTIR, and EDX. In addition, the surface topography of the nanofiber scaffold of MoO3/ginger@PLA showed that the nanofiber diameters differ from 0.085 to 0.34 µm. Furthermore, the contact angle of the water drop on the surface of the pure PLA and MoO3/CuO/GO/ginger@PLA is remarkably changed from 32.3° to 18.9°. Moreover, the cell viability test of the composition MoO3/CuO/GO/ginger@PLA is above the IC50 at all concentrations. Meanwhile, the antibacterial test exhibited antibacterial activity against E. coli and S. aureus for the scaffolds, with an inhibition zone of 23 ± 0.816 mm and 16.33 ± 0.942 mm for MoO3/CuO/ginger@PLA and 20.3 ± 0.471 mm and 15.33 ± 0.943 mm for MoO3/CuO/GO/ginger@PLA. The obtained results are appropriate to aid the cells to grow and proliferate. As a result of that, the fabricated scaffolds could be utilized in biomedical applications. [ABSTRACT FROM AUTHOR]

The presence of organic dye contaminations has been a major concern in recent years. Metal oxides and their composite have created a huge interest in the degradation of organic pollutants utilizing particularly direct sunlight has been investigated recently. This study demonstrated a facile sol-gel-assisted synthesis of copper oxide (CuO) nanoparticles (NPs) dispersed on reduced graphene oxide (rGO) composite for solar light-assisted removal of methylene blue (MB) dye and nanofluids applications. Transmission electron microscopic images displayed that the CuO NPs, which had a mean diameter of 30 nm, were dispersed on the rGO surface. The composite photocatalyst demonstrated a 92% degradation rate for MB dye. In addition, the study examined the impact of photocatalyst quantity, concentration of MB, and pH on MB degradation. A study on radical scavenging demonstrated that the generation of superoxide radicals was the main factor responsible for the degradation of MB. The stability test demonstrated that the degradation efficiency of the MB did not exhibit a substantial reduction after four consecutive cycles. Furthermore, the thermal conductivity of CuO/rGO nanofluids depends on the particle concentration and temperature. The thermal conductivity enhancement of the nanofluids with a 0.07% volume fraction at 65 °C in deionized water and ethylene glycol was found to be 47.5% and 30.3%, respectively. Highlights: Sol-gel synthesis of CuO/rGO composite for photocatalysis and nanofluids. The composite photocatalyst degraded 92% of MB dye in 90 min under sunlight. The ROS study confirmed that O2–• was the reason for MB dye degradation. The highest thermal conductivity was observed with a volume fraction of 0.07%. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the optimization of CuO and MgO nanoparticle reinforcement ratios within glass fiber‐reinforced polymer (GFRP) composites, and it examined the impact of the hybrid mixture of oxide powders on the mechanical properties of the GFRPs. The study aims to improve the mechanical properties of GFRPs by combining these two powerful nanofillers in various weight ratios to find the best combination to obtain the best fatigue life. Tensile‐tensile fatigue tests were conducted on 25 samples containing hybrid CuO and MgO nanoparticles ranging from 0.0 to 0.8 wt% in 0.2% increments. The test was conducted using a computer‐controlled servo‐hydraulic fatigue device. It was found that the GFRP composite reinforced with hybrid nanoparticles improved the fatigue life. The CuO proportion in the composites partially increased the brittleness properties, while the MgO proportion partially increased the stiffness according to the results. It was found that 0.6 wt% MgO–0.4 wt% CuO and 0.2 wt% MgO–0.6 wt% CuO GFRP composites demonstrated the highest fatigue life yielding at the 39.5k, and 13.7k cycle at 70%, and 80% load level, respectively. The best fatigue life was yielded at the 128k cycle with the 0.4 wt% MgO and 0.6 wt% CuO sample at the 60% load level. According to experimental hysteresis energy loss, 0.4 wt% MgO–0.2 wt% CuO GFRP composite was found to have the highest energy loss. The energy loss increased by approximately 51% in this composite compared to the non‐reinforced composite. The fracture surfaces of a fatigue sample were shown with the SEM image. Highlights: The GFRP composites were produced by combining MgO and CuO as a hybrid reinforcement.Analyzed fatigue life using hysteresis curves and S–N graphs.The fatigue life of GFRP composites was improved with hybrid nanofiller content.As compared to separate reinforcements with CuO or MgO, the hybrid nanoparticle reinforcement enhanced fatigue life more. [ABSTRACT FROM AUTHOR]

The effectiveness of copper oxide-modified electrochemical sensors using different polymers is being studied. The commercial powder was sonicated in an isopropyl alcohol solution and distilled water with 5 wt% polymers (chitosan, Nafion, PVP, HPC, α-terpineol). It was observed that the chitosan and Nafion caused degradation of CuO, but Nafion formed a stable mixture when diluted. The modified electrodes were drop-casted and analyzed using cyclic voltammetry in 0.1 M KCl + 3 mM [Fe(CN)6]3−/4− solution to determine the electrochemically active surface area (EASA). The results showed that α-terpineol formed agglomerates, while HPC created uneven distributions, resulting in poor stability. On the other hand, Nafion and PVP formed homogeneous layers, with PVP showing the highest EASA of 0.317 cm2. In phosphate-buffered saline (PBS), HPC and PVP demonstrated stable signals. Nafion remained the most stable in various electrolytes, making it suitable for sensing applications. Testing in 0.1 M NaOH revealed HPC instability, partial dissolution of PVP, and Cu ion reduction. The type of polymer used significantly impacts the performance of CuO sensors. Nafion and PVP show the most promise due to their stability and effective dispersion of CuO. Further optimization of polymer–CuO combinations is necessary for enhanced sensor functionality. [ABSTRACT FROM AUTHOR]

The fabrication of flexible electronics has gained extensive attention due to the growing demand of flexible devices. Among various methods, laser direct writing technology has emerged as a promising approach due to its advantages of high processing accuracy and simplicity. This research focuses on the preparation of copper microelectrodes using laser‐induced reduction of CuO nanoparticles (Cu NPs) on polyethylene terephthalate films. First, the influence of various parameters on the conductivity of the copper microelectrodes is investigated. Second, flexible copper microelectrodes with a minimum resistivity of 62.29 μΩ cm and an adhesion grade of 4B level are successfully fabricated. Building upon these results, a capacitive pressure sensor is developed with optimal sensitivity of 3.99 Pa−1, good hysteresis of 3.99%, and response and recovery times of 1.2 and 1.3 s, respectively. Repeatability tests confirm the sensor's stability and fatigue resistance. This research provides valuable insights for the production of flexible sensors. [ABSTRACT FROM AUTHOR]

This study involved depositing thin films of copper oxide (CuO) and copper oxide films incorporated with neodymium oxide (Nd2O3) in various weight ratios using the pulsed laser deposition technique to fabricate an ammonia gas sensor. The characteristics of the developed films were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and photoluminescence spectroscopy (PL) techniques. The study investigated the impact of incorporating Nd2O3 into the CuO film on its sensing characteristics. The X-ray analysis revealed a polycrystalline structure of CuO with a crystal size of 19 nanometers. Furthermore, incorporating CuO and Nd2O3 formed a mixed phase comprised of both CuO and Nd2O3. The average crystallite size varied with the Nd2O3 incorporation rate from 19nm to 14.7nm. With increasing Nd2O3 incorporation ratios, the surface morphology changed from smooth to spherical-like nanostructures, and the average particle sizes varied from 28nm to 130nm. The PL spectrum analysis results confirmed that the incorporation of Nd2O3 resulted in a change in the peak intensity of the PL spectrum, with a significant increase in the peak associated with oxygen vacancies, contributing to the improvement of the sensor response. The incorporation of Nd2O3 greatly enhanced the sensitivity of the as-deposited CuO film. The sample with 5 wt.% Nd2O3 exhibited the maximum sensitivity, reaching 180% against 79 ppm NH3 at a working temperature of 50∘C. [ABSTRACT FROM AUTHOR]

Undoped, Fe, Sn doped and Fe/Sn co-doped copper oxides are prepared by precipitation synthesis. X-ray diffraction confirmed that the all synthesized powders show a monoclinic main CuO phase. The insertion of Fe or/and Sn within the CuO matrix moderately affects the preferential growth direction. Basically Fourier Transform Infrared (FTIR) confirmed about functional group and their vibrations in the CuO samples. The reflectance of the undoped sample is higher than that of the other samples. Compared to undoped CuO, the doped and co-doped NPs exhibit red-shifted gap energy. Indeed, the Fe-doped, and Sn-doped CuO NPs, exhibit a slight decrease of gap energy (1.47, 1.45 eV respectively) compared to the undoped CuO (1.49 eV), while the Fe/Sn co-doped sample has a lower gap energy of 1.06 eV. Additionally, the antibacterial efficiencies of the all-synthesized samples are tested against Staphyloccus species. Doped and undoped CuO nanopowders show important antibacterial activity on tested bacteria with MICs values ranged between 0.039 to 1.25 mg/ml. Minimum Inhibitory Concentration value of 0.039 mg/ml was obtained with Fe-doped CuO NPs (CuO:Fe NPs) against S.aureus ATCC33591, whereas the highest MIC value of 1.25 mg/ml was obtained with CuO:Sn nanopowder against the strain S. epidermidis, which was the most resistant strain. Moreover, all CuO NPs, except CuO:Fe/Sn showed important anti-adhesive and antibacterial activities against S. epidermidis when used as pellets. This was confirmed either by cell counts using the determination of CFU/ml of bacterial suspension inside the hole, or by using fluorescence microscopy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Electrochemistry is the property of Journal of Electrochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AbstractComposite materials CuO/g-C3N4 (CuOCN) were prepared using a solvothermal method to investigate their degradation effect on ciprofloxacin (CIP). The materials were characterized through X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), UV-visible diffuse reflectance spectrophotometry (DRS), and X-ray photoelectron spectroscopy (XPS). The toxicity of degradation products of CIP was assessed through antibacterial experiments, and the degradation mechanism of CIP was investigated using quenching agent capture and high-performance liquid chromatography-mass spectrometry (HPLC-MS). The results of XRD and FTIR indicate that the CuOCN composite has been successfully synthesized. The photocatalytic experiment shows that adding 15% (w/w) of Cu3(BTC)2(H2O)3 in melamine (CuOCN2) has a relatively good degradation effect on CIP and can be reused multiple times. The TEM results indicate that both CuO and g-C3N4 have a layered structure and are attached together. HRTEM analysis reveals that the two components in CuOCN2 are arranged in a layered structure, with CuO displaying two crystal planes. Energy Dispersive Spectrometer (EDS) analysis reveals that the proportion of CuO in the three composite materials is 7.86% (w/w), 15.93% (w/w), and 84.83% (w/w), respectively. DRS detection reveals that the greater the amount of CuO added, the broader the visible light absorption range of the composite material, and the narrower the bandgap width. The photocurrent and photoresistance indicate that CuOCN2 exhibits a good photoelectric effect. XPS analysis shows that the CuOCN2 composite material possesses both the chemical composition and structure of CuO and g-C3N4. During the catalytic degradation process of CIP, four active substances, h+, e−, ·O2−, and ·OH, were produced, leading to a reduction in the toxicity of the degradation products. Through HPLC-MS analysis, it was found that CIP undergoes reactions such as defluorination, ring opening of piperazine, and quinolone during degradation, resulting in reduced toxicity. This study provides an experimental basis for the degradation of CIP by CuOCN2. [ABSTRACT FROM AUTHOR]

The laser ablation (PLA) method was used with different laser pulses to make copper oxide/polyvinyl alcohol (CuO/PVA) nanocomposite thin films. The effect of laser pulses on the optical, structural, morofigical, and roughness properties was investigated. X-ray diffraction (XRD) results confirmed the formation of CuO nanoparticles (NPs) after ablation of the target surface with a pulsed laser beam with high crystallinity and purity. The direction of crystal growth was in the (002) plane. [ABSTRACT FROM AUTHOR]

Herein, a green synthesis methodology for making copper oxide (CuO) nanoparticle clusters in a cost-effective and simple way is reported. While cuprous sulfate pentahydrate is used as a source of copper, the outer layer of green peas (Pisum Sativum) is used as a source of phenol. Extracting the phenol from pea peels is a simple process that uses water as a solvent. Copper salt is reduced by the phenolic content that is so produced. Both physicochemical and microscopic characterization Scanning Electron Microscope (SEM), and Energy-dispersive X-ray (EDX) analysis were performed on the particles. A variety of pea-peeling samples were used during the procedure's several executions to ensure reproducibility. The preparation process was appropriate, as the outcomes were identical. Analyses were also conducted on the produced particles' electrochemical activity as an application. A well-defined and organized redox reaction was seen at E' = +0.25 V against Ag/AgCl which were also shown to be highly electro-active. With the benchmarked redox mediator (5 mM ferricyanide), the particles also produced an outstanding redox peak at E1/2 = -0.01 V vs. Ag/AgCl. In a common reducing organic reaction, such as the reduction of p-nitro phenol to p-amino phenol, they were also found to be effective catalysts. Additionally, tests were conducted on the produced particles for their anti-bacterial and antifungal properties. Overall, a simple method for the formation of commercially viable CuO nanoparticle clusters is developed with the potential for diverse applications. [ABSTRACT FROM AUTHOR]

Belite-ye'elimite-ternesite (BYT) cement is a new type of cement with low energy consumption and carbon dioxide emissions. Notably, the sintering temperature of ye'elimite (C4A3$) is approximately 150 °C higher than that of ternesite (C5S2$) and belite (C2S). To facilitate the simultaneous presence of three minerals, the mineralizer (CuO) was used to reduce the formation temperature of C4A3$ in this work. Thermogravimetric (TG) was utilized to investigate the sintering temperature of minerals within the clinker. Furthermore, X-ray powder diffraction and scanning electron microscope were applied to analyze the phase composition and microstructure, respectively. The findings reveal that BYT cement clinker can be synthesized in one step at 1200 °C by adding 4% CuO. Ternesite (C5S2$) initiates hydration by 28 d, contributing to the stable development of medium-term strength. Optimal mechanical properties were observed with a ratio of C4A3$:C2S:C5S2$ at 40:50:10, achieving a 28 d strength of 43.7 MPa. [ABSTRACT FROM AUTHOR]

Creating polymer nanocomposite specimens is carried out using the solution-casting technique. The specimens are comprised of a host matrix of polyvinyl alcohol (PVA), in which varying concentrations of zirconium oxide (ZrO2) and copper oxide (CuO) nanoparticles are incorporated, spanning a range from 0 to 6 wt.%. The nanostructures composed of PVAZrO2-CuO exhibit notable attributes, such as low expenses, enhanced resistance to corrosion, favourable optical properties, and a relatively lightweight nature compared to alternative nanosystems. The optical properties are measured within the wavelength range (λ) from 200 nm to 840 nm. Optical properties show that the absorption coefficient, refractive index, and dielectric-constant real and imaginary parts for PVA-ZrO2-CuO nanocomposite increase with increasing concentrations of the ZrO2-CuO nanoparticles; so, the optical parameters at wavelength λ = 400 nm: absorption coefficient (α), refractive index (n), extinction coefficient (k), real (ε1) and imaginary (ε2) parts of dielectric constants, and optical conductivity (σop) for PVA are enhanced by about 1540%, 100%, 2216%, 302%, 1116%, and 3025%, respectively, with adding of 6 wt.% ZrO2CuO nanoparticles. The performance of the PVA-ZrO2-CuO nanocomposites suggests that they possess favourable characteristics as optical nanomaterials in the domains of electronics and optics [ABSTRACT FROM AUTHOR]