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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]

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 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]

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 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]

The present study reports on the preparation of a cellulose fiber (CF) composite from D. lutescens, combined with copper oxide nanoparticles (DL@CF/CuO), to prolong the shelf life of tomatoes after harvest. The isolated cellulose fiber material was comprehensively characterized using XRD, FTIR, and FE-SEM analyses. The DLCF and DL@CF/CuO nanoparticles exhibited crystalline cellulose, as indicated by the XRD investigation. Both DLCF and DL@CF/CuO showed O-H and C-H FTIR spectra with identifiable vibrational peaks. The FE-SEM images depicted the dispersion of DL@CF/CuO-based fibers in a cellulose fiber matrix containing CuO nanoparticles. A 0.3% (wt/wt), a solution of DL@CF/CuO was coated onto the surface of early ripening tomato fruits. After a 25-day storage period at 25–29 °C and 85% RH, the results showed a significant extension in the shelf life of the tomato fruits, in line with changes in physiological properties and fruit quality. The extension of shelf life in tomato fruit epidermis treated with DL@CF/CuO was confirmed through FE-SEM analysis. L929 fibroblast cells were treated with the developed DL@CF/CuO nanocomposite, and no signs of toxicity were detected up to 75 µg/mL. Additionally, the DL@CF/CuO nanocomposite exhibited significant antifungal activity against Aspergillus flavus. In conclusion, this study provides novel insights for sustainable food security and waste control in the agricultural and food industries. [ABSTRACT FROM AUTHOR]

The induction of cuproptosis, a recently identified form of copper‐dependent immunogenic cell death, is a promising approach for antitumor therapy. However, sufficient accumulation of intracellular copper ions (Cu2+) in tumor cells is essential for inducing cuproptosis. Herein, an intelligent cuproptosis‐inducing nanosystem is constructed by encapsulating copper oxide (CuO) nanoparticles with the copper ionophore elesclomol (ES). After uptake by tumor cells, ES@CuO is degraded to release Cu2+ and ES to synergistically trigger cuproptosis, thereby significantly inhibiting the tumor growth of murine B16 melanoma cells. Moreover, ES@CuO further promoted cuproptosis‐mediated immune responses and reprogrammed the immunosuppressive tumor microenvironment by increasing the number of tumor‐infiltrating lymphocytes and secreted inflammatory cytokines. Additionally, combining ES@CuO with programmed cell death‐1 (PD‐1) immunotherapy substantially increased the antitumor efficacy in murine melanoma. Overall, the findings of this study can lead to the use of a novel strategy for cuproptosis‐mediated antitumor therapy, which may enhance the efficacy of immune checkpoint inhibitor therapy. [ABSTRACT FROM AUTHOR]

A simple chemical method for producing ZnO/ CuO/ CdS nanoparticles using a chemical route (SILAR) method has been utilized. XRD patterns show hexagonal structures for ZnO, spheres, and cubic-formed CuO/CdS nanoparticles. Nanoparticles showed a blue shift in their UV-VIS energy band edge with (3.7, 3, and 3.2) eV for ZnO, CuO, and CdS. The morphology of ZnO, CuO, and CdS nanoparticles is investigated using scanning electronic microscopy (SEM). The XRD pattern reveals that the crystallites size are 15–30 nm. Photoluminescence reveals a yellow-green (520 nm) region for ZnO, a blue (380 nm) region for CuO, and a red (440 nm) region for CdS. The CdS wideband gap restricts its application. In this manner, we combined ZnO, CdS, and CuO for the band gap design of the heterojunction and to get improved optoelectronic properties. Present results show that heterojunctions could be useful for long-term usage and effective photodiode applications. [ABSTRACT FROM AUTHOR]

Herein, we report on the post-annealing temperature effect on the transport behavior of p-CuO/Al Schottky barrier diodes. In addition, the transformation of phase from Cu4O3 to CuO phase was studied. Copper oxide thin films were grown on soda lime glass substrates, and post-annealing temperature's influence on the films' structural, chemical, morphological, and electrical characteristics was comprehensively examined. X-ray diffraction study revealed the development of polycrystalline tenorite phase (CuO) on annealing. Raman analysis also confirmed the formation of the tenorite phase (CuO) at higher annealing temperatures (400 °C and 500 °C). XPS study revealed the occurrence of the Cu4O3 phase for room temperature deposited sample and CuO phase at the higher annealing temperature. Using current–voltage analysis, the Chueng model, and the thermoelectric emission model, the Schottky behavior between the metal and semiconductor were investigated. The fabricated diode showed a rectification ratio of 103 at ± 2 V, with the barrier height ranging from 0.84 to 1.12 eV due to different annealing treatments. The attributes of the power law were employed to elucidate space charge-limited conduction and the process of tunneling across the density of interface traps in p-CuO/Al Schottky diodes. This study provides valuable insights into the behavior of the p-CuO/Al Schottky junction, enhancing our understanding of its characteristics. [ABSTRACT FROM AUTHOR]

Polymethyl methacrylate (PMMA) with varied compositions of copper oxide (CuO) nanoparticles was synthesized using in‐situ free radical polymerization. UV–visible, FT‐IR, XRD, FE‐SEM, DSC, and TGA were employed to examine their structure, morphology, and thermal properties. The broadening and intensification of UV absorption, as well as the shift in IR peaks of PMMA with the addition of CuO, confirm their interactions. The reduction in optical bandgap values with the reinforcement of nanofillers confirms the existence of intermediate energy bands in nanocomposites. XRD indicated that polymerization with CuO reduced the amorphous nature of PMMA. The FE‐SEM image revealed that the dispersion of CuO altered the nonporous, rough surface of PMMA into a homogeneous shape. The reinforcement of CuO enhanced the thermal stability and glass transition temperature of PMMA. The mechanical strength, modulus, impact strength, and rigidity of PMMA were significantly improved through in‐situ polymerization. The electrical property analysis revealed that the AC conductivity increased with frequency, temperature, and filler content. The reduction in activation energy of AC conductivity with temperature points toward their semiconducting nature. PMMA/CuO nanocomposites with higher tensile strength, lower bandgap energy, higher conductivity, and thermal properties can be used to make flexible optoelectronic devices. Highlights: A series of PMMA/CuO nanocomposites were synthesized and characterized.Enhanced optical property, thermal stability, and glass transition temperature.Possess excellent dielectric constant and AC conductivity.Mechanical strength and impact resistance of PMMA were greatly enhanced.A promising material for flexible optoelectronic and power storage applications. [ABSTRACT FROM AUTHOR]

In these studies, radio frequency (RF) magnetron sputtering was used to produce nanostructured CuO thin films on glass bases with different thicknesses of (250, 300, and 350 nm). X-ray diffraction (XRD) analysis of these films revealed a polycrystalline structure with a preferred peak along the (111) plane. The Scherrer formula was used to compute the grain size. It was found that the average grain sizes are 10.78 nm, 11.36 nm, and 11.84 nm for film thicknesses of 250, 3000, and 300 nm, respectively, while the dislocation density and strain values decline. The surface roughness decreased from 9.30 nm to 4.71 nm as the thickness increased, according to atomic force microscopy (AFM) data. As the thickness of the film grew, the root mean square (RMS) roughness likewise decreased from 9.18 nm to 4.29 nm. The homogenous, semi-spherical structure comprises uniformly distributed particles, as demonstrated by SEM images. The optical properties of the grown films showed that the absorption coefficient considerably increased with film thickness. Transmittance, band gap, refractive index, and extinction coefficient all decrease with increasing film thickness. The hydrogen gas measurements, indicated a reduction in sensitivity as the thickness and gas concentration increased at 30°C. [ABSTRACT FROM AUTHOR]

In the present work, structural, optical, and electrical properties of lithium-doped (0-6 at.%) copper oxide thin films were investigated. The films were obtained by the spray pyrolysis method on glass substrates at 450°C. The X-ray diffraction method, UV-visible spectroscopy, and the four-point probe technique were used to analyze the films. Based on the X-ray diffraction investigations, it was found that the polycrystalline films have monoclinic phases with preferred (111) and (111) crystallographic planes. The incorporation of lithium doping into the copper oxide thin film yielded crystallite sizes of approximately 2 nm. The estimated optical band gap values are decreased from 1.88 to 1.64 eV with increasing lithium concentration. Four-point probe studies revealed that the resistivity of the films decreased from 339 to 186 Kcm with increasing lithium concentration. [ABSTRACT FROM AUTHOR]

Copper oxide is one of the original semiconductor materials employed for solar cells in the early 19th century before Silicon solar cells became popular due to their abundant availability, and eco‐friendly nature. The optoelectronic parameters signify its huge potential in solar cell devices, though it's far from the theoretically predicted performance, provides tremendous scope to improve the solar cell performance by forming different heterojunctions. In this study, we investigated the copper oxide's (CuO) potential as an active layer in thin‐film solar cells theoretically with a new structure consisting of a Glass/ITO/Graphite/CuO/Ni. Furthermore, the charge carrier's generation rate and theoretical thresholds for photovoltaic device efficiency were determined for varying active layer thicknesses by employing a normalized light intensity equivalent to that of the AM1.5 spectrum. The optimized performance of the simulated structure by considering realistic optical parameters of the solar cell was ~24%, obtained for the 500 nm CuO films. The performed theoretical work can help to employ CuO and boost the performance of solar cells experimentally. [ABSTRACT FROM AUTHOR]

In this study, due to the importance of Melt-Blown nonwoven fabrics (MBNWF) for air purification and public health, nanomaterials of net CuO and Fe-doped in CuO structure were used to create antibacterial properties of MBNWF. The aforementioned nanomaterials were synthesized as an antibacterial agent by hydrothermal method and characterized by X-ray diffraction (XRD), energy dispersive X-ray (EDX) and Field Emission Scanning Electron Microscopy (FESEM) analyses. The results showed that CuO and Fe-doped CuO were polycrystallized with a monoclinic nanosheet structure without impurities. Next, the MBNWF were coated with these nanosheets (NSs) in a simple process using an autoclave. Fabric samples were analysed by FESEM to confirm coating performance. The viable Cell Count method was used to test the antibacterial effect of the samples. The results showed that the samples have strong antibacterial properties against Staphylococcus aureus (Gr+) and Escherichia coli (Gr−) bacteria strains. In most cases, the inhibition efficiency observed was above 90%. [ABSTRACT FROM AUTHOR]

The composites of some transition metal oxides are currently attracting interesting roles in various fields of technology and industry. The present work attempts to tune the properties of copper oxide (CuO) for hydrogen energy generation. Iron (Fe) and cobalt (Co) were intentionally doped at precise contents into CuO thin films. X-ray diffraction (XRD) indicated that the successful substitution of Fe and Co on the Cu sites created induces pressure (tensile) stress in the lattice. Fe doping deteriorated the films' crystallinity and increased the dislocation density from 1.82 × 10−3 to 4.36 × 10−3 nm−2, while Co codoping displayed unsystematic behavior. The scanning electron microscope (SEM) images showed that the films have smooth surfaces comprising a huge number of particles/unit area with a narrow size distribution. The energy-dispersive X-ray (EDX) analysis confirmed the presence of both Fe and Co with almost the pre-calculated ratios. The optical measurement showed that increasing the Fe contents increases the absorption coefficient of CuO and narrows its optical band gap from 1.7 to 1.55 eV. The photoluminescence (PL) intensity increases for Fe-doped CuO films whereas quenched when doped with Co. A series of photoelectrochemical (PEC) measurements were conducted to evaluate the performance of the prepared films in the production of solar hydrogen. The CuO–6%Fe film showed high photocatalytic performance for H 2 generation from H 2 O splitting over a wide wavelength range of sunlight with long-term photostability. The photocurrent density of CuO–6%Fe film is about 155 times more than those obtained from pure CuO film. The incident photon-to-current efficiency (IPCE) and the solar-to-hydrogen efficiency (η STH) of CuO–6%Fe film were 5.98 % at 307 nm and 0.94 % under Xenon illumination, respectively. Hence, this work proposed an efficient and reasonable technique to enhance the performance of a CuO-based photoelectrode for solar hydrogen production. [Display omitted] • Pure, Fe-doped, and (Fe, Co) codoped CuO photoelectrodes are made by spin coating. • The structural and morphological features of photoelectrodes are studied. • The performance of the photoelectrodes for solar H 2 production is evaluated. • Fe- and (Fe, Co)- doping affect optical and electric properties. • Solar to-hydrogen conversion efficiencies are estimated, and electrode stability is addressed. [ABSTRACT FROM AUTHOR]

In the article, results of dissolution of metal oxides using a natural deep eutectic solvent (NDES or NADES) based on betaine, malic acid and ethylene glycol are presented. The obtained deep eutectic solvent was characterised by determining its physicochemical properties including density, viscosity as a function of temperature. The thermal stability of NADES was also determined. For CuO, equilibrium, kinetics, and thermodynamics of the oxide dissolution process in NADES and H 2 O were determined. Dissolution studies of selected metal oxides including ZnO, MgO, CaO, Fe 2 O 3 in NADES and water were also carried out. It was found that the solubility of the metal oxides was 2 to 100 times higher in NADES compared to the solubility in water, despite the neutral pH of NADES. The study, using XRD and SEM methods, also shows changes in the morphology of particles subjected to dissolution in water and in NADES. The results indicate the possibility of extracting metal oxides by dissolution in NADES. [Display omitted] • Betaine, malic acid and ethylene glycol form a natural deep eutectic solvent NADES. • NADES-based solvent dissolves CuO, ZnO, MgO, CaO, Fe 2 O 3 2-100 times better than H 2 O. • The equilibrium, kinetics, thermodynamics of CuO dissolution in NDES were defined. • The results indicate the possibility of extracting MeO x by dissolution in NDES. [ABSTRACT FROM AUTHOR]

B-doped zinc oxide/copper oxide composites prepared using a simple method showed high photocatalytic hydrogen production activity in the presence of aqueous sulfide solutions. Co-modification of the CuO composite with B-doping caused an increase in the charge separation efficiency and light absorption capacity. The sacrificial effect was thermodynamically enhanced by manipulating the composition of the sulfide solution. A maximum hydrogen production activity of 224 μmol g−1 h−1 was achieved under 450 nm light irradiation in a photocatalytic system with optimized B doping, a CuO composite, and a sulfide sacrificial agent concentration. [ABSTRACT FROM AUTHOR]

The laser ablation technique was utilized to fill the carboxy methyl cellulose (CMC) solution with zirconium dioxide (ZrO2) and copper oxide (CuO) nanoparticles with different concentrations. Different techniques have been used to study the physical behavior of fabricated compositions. CuO has shown different peaks at related to the monoclinic phase of the prepared CuO NPs lattice constants (JCPDS No. 02-1225). According FTIR results, ZrO2 has exhibited vibrating bands at 460 cm−1, 477 cm−1, 670 cm−1, and 690 cm−1 which are corresponding to Zr–O vibration. In addition, CuO has shown vibrating bands at 439, 494, and 594 cm−1. The dielectric properties have been investigated. The TGA results showed that the sample CMC-ZrO2-CuO/20 min has excellent thermal stability as the weight loss is 36% of its initial weight at 796 °C. The optical and electrical characterization showed that the addition of ZrO2 and CuO has changed and enhanced the electrical characterization of CMC. The enhancement in electrical conductivity of the system encourages it for electrical applications. [ABSTRACT FROM AUTHOR]

3D electrode design is proposed as an attractive approach to simultaneously increasing energy and power densities for all-solid-state thin film lithium microbatteries (TFBs). However, currently reported TFBs based on 3D electrodes prepared by atomic layer deposition or physical vapor deposition suffer from relatively low areal capacity and high fabrication cost. In this work, a 3D CuO nanowire array electrode with controllable thickness is directly prepared on a conductive substrate by a facile wet chemistry route, based on which a high-performance CuO/LiPON/Li TFB is efficiently constructed. Possessing abundant electrode/electrolyte interface contact, shortened ion diffusion length, and accommodation capability for volume change, the CuO/LiPON/Li TFB exhibits a large areal capacity (92 μAh cm−2 at 15 μA cm−2), high rate capability (11 μAh cm−2 at 960 μA cm−2), and good cycle performance (nearly no capacity loss after 70 cycles). This work establishes the great potential of preparing 3D electrodes by wet chemistry routes for realizing high-performance TFBs. [ABSTRACT FROM AUTHOR]

Nanoparticles of CuO have been synthesized by the sol-gel technique and their structural, optical and chemical properties were studied to assess their antibacterial properties. These nanoparticles were found to be excellent antibiotic against E.coli and cocci gram-positive. Graphene oxide (GO) nanoparticles were also synthesized by hummers modified method and their optical, chemical and structural properties were confirmed. A composite of CuO and GO has also been prepared by sonication method. Using laser interferometry its ultraviolet (UV)-visible (VIS) spectrum has been observed to be consistent with its reference UV-VIS spectrum, which verified the formation of nanocomposite. The composites were prepared in suspension form, and were used for antibacterial activity, appeared to be a great antibacterial substance against two different types (E.coli and pseudo) of gram-positive bacteria. [ABSTRACT FROM AUTHOR]

CuO pricky microspheres have been synthesized without additives by calcination after hydrothermal treatment at 1 2 0 ∘ C for 6 h. The product was characterized by SEM, TEM, EDS, etc. The unique pricky microspheres were formed with NH4HCO3 and urea as precipitators. Through a series of reaction experiments, the possible formation mechanism of nucleation, growth and secondary growth was proposed. With the assistance of H2O2, the degradation rate of RhB aqueous solution reached 87.16% after 50 min by simulated visible light degradation, which proved the good photocatalytic performance of the CuO pricky microspheres. After four cycles of degradation experiments, the degradation rate of RhB aqueous solution is still above 80%. The radical capture experiments showed that the main active groups in the degradation process were ⋅OH and ⋅ O 2 − , and the mechanism of photocatalytic degradation of Rhb was proposed. [ABSTRACT FROM AUTHOR]

In this experimental work is based on the comparison on the three different nanoparticle mixed nanofluid usage influence on the evacuated tube solar collector (ETSC). The distilled water is initially tested to identify the better performance providing mass-flow rate then the mass-flow rate. There are three nanoparticles such as MWCNT, Al2O3, and CuO were used in to create the nanofluid by two step method to use as a heat transfer fluid in the system. There are four different combinations of nanofluid were created based on the 0.05% of volume fraction of nanoparticles involvement. The corresponding performance parameters such as outlet temperature, maximum absorbed heat and thermal efficiency were measured and calculated. Among that 50% of MWCNT, 40% of Al2O3, and 10% of CuO nanoparticle mixer of 0.05% volume fraction used nanofluid reached the 38.76% higher temperature difference 33.02% more useful heat absorbed and 33.04% of more efficiency than distilled water in the system. [ABSTRACT FROM AUTHOR]

Copper oxide nanowires (NWs) are promising elements for the realization of a wide range of devices for low-power electronics, gas sensors, and energy storage applications, due to their high aspect ratio, low environmental impact, and cost-effective manufacturing. Here, we report on the electrical and thermal properties of copper oxide NWs synthetized through thermal growth directly on copper foil. Structural characterization revealed that the growth process resulted in the formation of vertically aligned NWs on the Cu growth substrate, while the investigation of chemical composition revealed that the NWs were composed of CuO rather than Cu2O. The electrical characterization of single-NW-based devices, in which single NWs were contacted by Cu electrodes, revealed that the NWs were characterized by a conductivity of 7.6 × 10−2 S∙cm−1. The effect of the metal–insulator interface at the NW–electrode contact was analyzed by comparing characterizations in two-terminal and four-terminal configurations. The effective thermal conductivity of single CuO NWs placed on a substrate was measured using Scanning Thermal Microscopy (SThM), providing a value of 2.6 W∙m−1∙K−1, and using a simple Finite Difference model, an estimate for the thermal conductivity of the nanowire itself was obtained as 3.1 W∙m−1∙K−1. By shedding new light on the electrical and thermal properties of single CuO NWs, these results can be exploited for the rational design of a wide range of optoelectronic devices based on NWs. [ABSTRACT FROM AUTHOR]

Using the Wien2k code based on Full Potential Linearized Augmented Plane Wave approach, the density functional theory was used to examine the structural and opto-electronic properties of CuO. The 4D-optimize option and the Perdew–Burke–Ernzerhof (PBE)-sol functional are used to optimize the structural parameters. Generalized Gradient Approximation (GGA) with PBE-scheme along with the screened Coulomb interaction (GGA + U) and modified Becke–Johnson (GGA–TB-mBJ) potential was performed for the overall calculations. The computed band energies were taken as the key input to extract the transport properties with the help of the Boltzmann transport equation. In contrast to the gap energy provided by the GGA + U ( E g = 1. 5 7 eV), it is demonstrated that the gap energy produced by the TB-mBJ is ∼ 2. 0 2 eV, which is close to the experimental data. The optical characteristics show a high absorption coefficient in the ultraviolet region, an average transmittance of about 65% in the visible range, which covers a wide spectrum of light, and an average reflectance of about 18% in visible light. At low temperatures, the carrier mobility limits the CuO conductivity, whereas, at high temperatures, the carrier concentration dominates. CuO is a potential material for solar cell applications as an absorbent layer and antireflection coating due to these characteristics. [ABSTRACT FROM AUTHOR]

Environmental pollution is a global problem and dye pollution is one of the major factors. TiO2 shows promising photocatalytic properties that can degrade organic pollutants such as dye under ultraviolet (UV) irradiation. However, TiO2 possesses some disadvantages such as a wide band gap and a high recombination rate of electron-hole pairs. Coupling TiO2 with various metal oxides can enhance photocatalytic properties. In this work, photodepositon (reduction of metal ions on TiO2) followed by the thermal oxidation method were used for the coupling of TiO2 with CuO, ZnO, or SnO2 under various methanol concentrations (25 vol% or 50 vol%) and deposition duration (1 h or 3 h) to observe the effect of these parameters on the photocatalytic degradation activity on Rhodamine B (RhB) dye (up to 90 min). The rate constant of the photodegradation reaction (k) has improved from 0.0141 min−1 (uncoupled TiO2) to 0.0151~0.0368 min−1. Overall, CuO/TiO2 and SnO2/TiO2 samples have shown similar photocatalytic properties (average rate constants of 0.0341 min−1 and 0.0327 min-1, respectively), and both performed better than ZnO/TiO2 in terms of RhB photodegradation (average rate constants of 0.0197 min−1). The difference in photocatalytic performance can be explained by the bandgap of metal oxides and their relative band positions with TiO2. Lastly, CuO/TiO2 (50 vol%, 3 h) and SnO2/TiO2 (50 vol%, 3 h) have shown the best photocatalytic properties respectively due to a longer deposition time and higher concentration methanol, resulting in more deposited materials. [ABSTRACT FROM AUTHOR]

For this article, waste glass cullet obtained from the glass industry was used as a choice of SiO2 substitute in glass manufacturing. A series of soda lime silicate glasses doped with CuO, in composition (55−x) SiO2: 15Li2O: 20Na2O: 10CaO: xCuO (x = 0.00, 0.01, 0.02, 0.03, 0.04, and 0.05 mol%)) were prepared by melt-quenching technique. The parameters such as density and molar volume were measured and evaluated their oscillator strength, refractive index, ion concentration, polaron radius, and inter-nuclear distance. Optical properties such as refractive index, absorption spectra, optical band gab, and CIE L*a*b* were investigated. With increasing of CuO concentration, the density and the refractive index of glasses increased, while the molar volume decreased. The absorption spectra show board peak in the range of 550 to 950 nm. The addition of CuO generated the blue hue in glasses, corresponding to the CIE L*a*b color coordinate. [ABSTRACT FROM AUTHOR]

Although the generation of hydrogen by electrolysis of water is cheapest from all other available sources but splitting of water still takes place with sluggish kinetics and is a challenging barrier for H 2 production on large scale. Moreover, research work is still in progress to understand the oxygen evolution reaction (OER) and design the catalysts with improved OER performance. Herein, we report synthesis, characterization, and OER performance of copper oxide/copper sulfide (CuO/CuS) heterostructures and its individual components copper oxide (CuO) and copper sulfide (CuS) as low-cost catalysts for water oxidation. CuO/CuS has been demonstrated to be a stable and effective catalyst that initiates the OER at a potential of 1.49 V. (vs. RHE). The CuO/CuS catalyst drives the OER at only 270 mV overpotential and Tafel slope of 67 mV dec−1 with a current density of 10 mA cm−2 in 1.0 M KOH. CuO/CuS heterostructures outperforms OER performance of previously reported Cu-based catalysts. Long-term stability and performance toward OER are demonstrated by the oxygen evolution at an applied potential of 1.65 V (vs. RHE) over an extended period. This feature brings a favourable, non-noble, highly efficient, and robust OER catalyst. [Display omitted] • Cuo/CuS heterostructures catalyst synthesized for oxygen evolution reaction (OER). • It exhibits enhanced OER performance with overpotential of 270 mV@10 mAcm−2. • Pre-oxidation of water generate active Cu3+ centers which boost OER performance. • Heterostructures provide large surface area which is responsible for enhanced OER. [ABSTRACT FROM AUTHOR]

As supported CuO is well-known for low temperature activity, CuO/CeO2 nanosphere catalysts were synthesized and tested for CO oxidation and preferential oxidation of CO (PROX) in excess H2. For the first reaction, ignition was observed at 95 °C, whereas selective PROX occurred in a temperature window from 50 to 100 °C. The catalytic performance was independent of the initial oxidation state of the catalyst (CuO vs. Cu0), suggesting that the same active phase is formed under reaction conditions. Density functional modeling was applied to elucidate the intermediate steps of CO oxidation, as well as those of the comparably less feasible H2 transformation. In the simulations, various Cu and vacancy sites were probed as reactive centers enabling specific pathways. [ABSTRACT FROM AUTHOR]

The development of highly effective dressing materials for human injuries that meet the complex requirements for clinical examination is still a challenge. In this regard, different biomaterials could be examined for wound dressing targets. Among these materials, polycaprolactone (PCL) is high biocompatible polymeric substance and has been used for numerous pharmaceutical applications. Furthermore, targeting antibacterial behavior could be done by merging additional nanoparticles such as copper oxide (CuO) and vanadium Oxide (V 2 O 5). The scaffolds could be fabricated using the cast method, which is one of the most simple and facile methods. The morphological features and the surface roughness of the fabricated could be examined using X-ray diffraction, Raman spectroscopy, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) tests. The contact angle plays a significant role in studying the wettability of the scaffolds and the hydrophilic or hydrophobic behavior of the composed films. Besides the antibacterial behavior to evaluate the effectiveness of these scaffolds to protect the injury until the healing. The cell viability against human normal cells to examine the biocompatibility of the proposed compositions. In this regard, the topographical images show a smooth surface with random pores that have diameters in the range of 0.5–1.5 μm for pure PCL while, the porosity decreased with the addition of ginger and V 2 O 5. The blend of CuO/V 2 O 5 /ginger@ PCL represents a noticeable increase in porosity with a diameter between 0.5 and 3 μm. The contact angles were recorded respectively at 55.02°, 54.12°, 53.89°, and 53.71° which refer to the tendency of the scaffolds to the hydrophilic behavior. In addition, the anti-bacterial activity of CuO/V 2 O 5 /ginger@PCL was represented with the diameter of the inhibition zone equal to 17.6±1.2 mm for E. coli and 12.3±1.2 mm for S. aureus. [ABSTRACT FROM AUTHOR]

Three types of CuO with different micro–structures were applied to catalyze the conversion of glycerol to lactic acid. The structure–activity relationship between CuO and its catalytic performance was investigated by combining experiments and theoretical calculations. We demonstrated that two CuO samples (CuO–BCC and CuO–CA), as prepared by calcining copper salts, show larger lattice spacing than that of commercial CuO (CuO–COM). In the catalytic experiments, CuO–BCC, which had the largest lattice spacing (d = 0.2480 nm), exhibited the highest yield of 78.54% for lactic acid. The lattice strain caused by lattice expansion was considered more favorable for CuO–BCC in adsorbing glycerol molecules, thereby improving the conversion of glycerol to lactic acid. The DFT simulation calculation results further prove that CuO–BCC has a larger adsorption energy for glycerol and a smaller thermodynamic energy barrier for the dehydrogenation of glycerol to form the key intermediate products (glyceraldehyde and 1,3-dihydroxyacetone) than CuO–COM. This study demonstrates the role of lattice strain effects in the development of catalysts and provides ideas for catalytic glycerol-selective oxidation studies. [ABSTRACT FROM AUTHOR]

In present work, nanocomposites films of polyethylene oxide (PEO), copper oxide (CuO) nanoparticles and indium oxide (In2O3) nanoparticles have been fabricated for discoloration and photo-degradation of dyes pollutants with high efficiency, few cost, anti-aggregation and high dispersion of nanoparticles. The structural and optical properties of PEO/CuO–In2O3 nanocomposites have been investigated. The structural properties were included the tests: optical microscopic (OM), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The optical properties of PEO/CuO–In2O3 nanocomposites were studied in wavelength range (200–800) nm. The results of optical properties of PEO/CuO–In2O3 nanocomposites showed the absorbance of PEO increases about 57.4% at (λ = 500 nm) and the energy gap of PEO reduces about 41.1% with adding of CuO–In2O3NPs which may be considered as a key for various optical and electronic fields. The optical constant of PEO were improved by adding of CuO NPs and CuO–In2O3 NPs. The PEO/CuO–In2O3 nanocomposites have been utilized for photo-degradation of dyes pollutants. The results showed prepared nanocomposites can be used for excellent photo-degradation of dyes with high efficiency reached 91% and low concentration of nanoparticles. [ABSTRACT FROM AUTHOR]

In present work, the nanostructures of silicon carbide(SiC) and copper oxide(CuO) doped transparent polymer(PVA) were designed to employ in various nanosemiconductors and optics devices with excellent optical and electronic properties compared of others nanosystems. The optimized geometrical parameters, electronic and spectroscopic properties of PVA/SiC/CuO nanostructures were investigated. The optimization parameters included both bonds and angles. The structural and electronic properties involved the (total energy, electronic state, energy gap, electrochemical hardness, electronic softness and electrophilicity) as well as spectral properties, which involved IR and UV–Visible. The results showed good obtained relax for nanocomposites from the used density functional theory (DFT). The results indicated that the nanocomposites have high electronic softness and electrophilicity with lower electrochemical hardness. The addition of SiC leads to decrease the energy gap from 7.184 to 2.604 eV while the addition of CuO reduces the energy gap from 7.184 to 4.229 eV, these global results gave important electronic applications. Finally, the obtained results showed that the PVA/SiC/CuO nonocomposites have good structure, optical and electronic properties which make them can be useful as nanosemiconductors materials to use in many nanoelectronics and optics applications. [ABSTRACT FROM AUTHOR]

Highlights: S-doped CuO nanorod arrays (S-CuO/CF) constructed by sulfur leaching and oxidative remodeling strategy require only 1.23 and 1.33 V versus hydrogen evolution reaction (HER) to provide glycerol oxidation currents of 100 and 500 mA cm−2. S-CuO/CF shows satisfactory performance (at 100 mA cm−2, Vcell = 1.37 V) assembled as the anode in asymmetric coupled electrolytic cell of glycerol oxidation reaction and HER. The study identifies the key factors involved in the GOR reaction pathway, which include the C–C bond breaking and lattice oxygen deintercalation steps. Glycerol (electrochemical) oxidation reaction (GOR) producing organic small molecule acid and coupling with hydrogen evolution reaction is a critical aspect of ensuring balanced glycerol capacity and promoting hydrogen generation on a large scale. However, the development of highly efficient and selective non-noble metal-based GOR electrocatalysts is still a key problem. Here, an S-doped CuO nanorod array catalyst (S-CuO/CF) constructed by sulfur leaching and oxidative remodeling is used to drive GOR at low potentials: It requires potentials of only 1.23 and 1.33 V versus RHE to provide currents of 100 and 500 mA cm−2, respectively. Moreover, it shows satisfactory comprehensive performance (at 100 mA cm−2, Vcell = 1.37 V) when assembled as the anode in asymmetric coupled electrolytic cell. Furthermore, we propose a detailed cycle reaction pathway (in alkaline environment) of S-doped CuO surface promoting GOR to produce formic acid and glycolic acid. Among them, the C–C bond breaking and lattice oxygen deintercalation steps frequently involved in the reaction pathway are the key factors to determine the catalytic performance and product selectivity. This research provides valuable guidance for the development of transition metal-based electrocatalysts for GOR and valuable insights into the glycerol oxidation cycle reaction pathway. [ABSTRACT FROM AUTHOR]

The catalytic transfer hydrogenation (CTH) of bio-oil over CuO/PC (porous carbon) with the solid residue produced during biomass pyrolysis as the carrier was investigated with methanol as the hydrogen donor. The effect of carbonization temperature, activation temperature, KOH solution and metal loading on the physicochemical characteristics of CuO/PC catalystand catalytic transfer hydrogenation of bio-oil were investigated. The main alcohols formed in the CTH of bio-oil were 1, 4-butanediol, 1, 3-cyclopentadiol, 1, 3-cyclohexanediol, 2-cyclohexenol and alcohols. It was revealed that more alcohols were produced over CuO/PC using less Cu(NO 3) 2 than Cu 2 Al considering their favorable porous system. The well-developed pore structure is formed in PC at a higher calcination temperature and the concentration of activator, which was favorable for the CTH of bio-oil. Under the optimized preparation conditions, the mesopores accounting for 50% in the total pores, achieving the maximized yield of alcohols of 81%, and the well recycling performance was observed with the overall yield of alcohols decreases within 3% after five cycles because of the greater mesopores ratio. The biochar-based PC catalyst in this work enhances the effective usage of biomass to produce alcohols, fully conforming to the theme of energy conservation and low-carbon times. [Display omitted] [ABSTRACT FROM AUTHOR]

A simple and environmentally‐friendly approach was developed to synthesize 2D CuO nanosheets using electrochemical deposition. The formed 2D CuO nanosheets (NSs) exhibit numerous advantageous properties such as no toxicity, high electrical conductivity, large active surface area, and a p‐type semiconducting nature with a band gap of 1.2 eV. A sensitive electrochemical sensor was constructed for the amperometric detection of glucose to take advantage of these characteristics. The fabricated sensor displayed an excellent sensitivity of 2710 μA mM−1 cm−2 along with a wide linear range of 0.001–1.0 mM and a lower limit of detection of 0.8 μM (S/N=3). Additionally, the modified electrode possesses high selectivity and good stability. The outstanding electrocatalytic performance of the electrode is attributed to a large active surface area, unique structural morphology, and the high conductivity of the 2D CuO nanosheets. [ABSTRACT FROM AUTHOR]

Free radical scavenging property of different ligand directed nanostructures of CuO (rod‐, sphere, flower‐, and star‐shaped) prepared through aqueous based chemical precipitation route using various carboxylic acids (viz. tartaric acid, citric acid and acetic acid) have been investigated using N,S co‐doped carbon dots (NSCDs) as a novel fluorescent probe which is validated through diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging assay and EPR study. The rod shaped nanostructures having the highest negative surface potential and lowest BET surface area compared to other morphologies, were found to show the highest radical scavenging ability which was corroborated with the maximum decrease of the DPPH absorption peak in UV‐vis spectra, largest attenuation of the DPPH free radical signal in EPR intensity and the maximum quenching of the fluorescent intensity of the NSCDs probe. [ABSTRACT FROM AUTHOR]

A flexible and portable triboelectric nanogenerator (TENG) based on electrospun polyvinylidene fluoride (PVDF) doped with copper oxide (CuO) nanoparticles (NPs, 2, 4, 6, 8, and 10 wt.-% w.r.t. PVDF content) was fabricated. The structural and crystalline properties of the as-prepared PVDF-CuO composite membranes were characterized using SEM, FTIR, and XRD. To fabricate the TENG device, the PVDF-CuO was considered a tribo-negative film and the polyurethane (PU) a counter-positive film. The output voltage of the TENG was analyzed using a custom-made dynamic pressure setup, under a constant load of 1.0 kgf and 1.0 Hz frequency. The neat PVDF/PU showed only 1.7 V, which further increased up to 7.5 V when increasing the CuO contents from 2 to 8 wt.-%. A decrease in output voltage to 3.9 V was observed for 10 wt.-% CuO. Based on the above results, further measurements were carried out using the optimal sample (8 wt.-% CuO). Its output voltage performance was evaluated as a function of varying load (1 to 3 kgf) and frequency (0.1 to 1.0 Hz) conditions. Finally, the optimized device was demonstrated in real-time wearable sensor applications, such as human motion and health-monitoring applications (respiration and heart rate). [ABSTRACT FROM AUTHOR]

Although significant advances have been witnessed in the application of nanozymes in recent years, exploring new strategies to enhance the enzyme-like activity of nanozymes is of urgent importance. Herein, we investigate the feasibility of accelerating the peroxidase-like reaction rate of CuO nanostructures through Fe doping. The coprecipitation method was used to synthesize Fe-doped CuO (Fe-CuO) nanozymes, and the results indicate that the diversified valence of Fe benefits the redox reaction driven by CuO-based nanozymes. With the improved peroxidase-like activity, the Fe-CuO nanozyme enables the significant chromogenic oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB), facilitating the construction of a visual sensing platform for the sensitive and selective determination of ascorbic acid. Under optimal conditions, the absorbance at 652 nm decreases linearly with the concentration of ascorbic acid in the range of 5–50 μM, with a limit of detection as low as 4.66 μM. This work exemplifies the activity enhancement for peroxidase-mimicking nanozymes with a metal-doping strategy and provides a broad prospect for the design of more high-performance nanozymes for biosensing applications. [ABSTRACT FROM AUTHOR]

The effect of the energy, the interval between the pulses, and the number of double laser pulses on the formation of the component and charge composition of laser plasma by laser spark spectrometry (LSS-1 spectrometer) was studied. The processes leading to the formation of mixed nanopowders of copper and aluminum oxides, precursors for the production of nanoceramics and films of CuAlO2 copper aluminates by the action of double laser pulses on a hybrid target consisting of cemented aluminum and copper plates, from AD1 and M2 alloys were investigated. It was shown that precursors for the manufacture of nanoceramics and nanofilms of CuAlO2 copper aluminates can be obtained by the successive action of a series of double laser pulses with energy of 53 mJ and an interval of 10 μs on a hybrid target. A closed glass weighing bottle containing the target was used for the products formed during interaction of the aluminum and copper ions with atmospheric oxygen. The size of the initial particles, determined by means of a high-resolution electron microscope, amounted to 30–45 nm. The particles were assembled into agglomerates and had a crystalline structure and spherical form. On account of the purely diffusion transfer mechanism of the fractals the size and amount of the fractal aggregates settling on the support situated at the bottom of the cuvette were several times greater than the amount of the products that settle on the side support. The main contribution to change in the intensity of the spectral lines for the Al and Cu atoms and ions and the AlO molecular bands comes from interaction of the second pulse with the condensation products formed in the channel after the action of the first pulse. With increase in the number of long-lived fractal aggregates in the air the intensity of molecular bands and lines decreases by ~1.5 times for Al III and by ~2 times for copper, which is due to active interaction of the long-lived large fractals that accumulate in the air with the incident radiation. [ABSTRACT FROM AUTHOR]

The issue of industrial dyes has risen to the forefront of environmental concerns, as they are now recognized as a prevalent form of industrial waste that pollutes our surroundings. As such, it is imperative that efforts be made to address their toxicity, with a view to safeguarding the environment and public health. To this end, the application of nanotechnologies presents a promising solution to the challenge of mitigating the harmful effects of industrial dyes on our environment. Copper oxide nanoparticles (CuO NPs) have been found to possess strong photocatalytic properties and are effective in degrading toxic dyes in polluted water and industrial effluents. In this experimental work, CuO NPs were synthesized using Citrus limon leaves extract as source of bioactive molecules to obtain stable NPs. Microscopic and spectroscopic analyses confirmed the formation of CuO NPs with size range of 20–25 nm with spherical shape. In addition, the prepared NPs utilized as photocatalyst against Remazol Brilliant Blue R (RBBR) dye, which shows remarkable potency within 180 min with degradation efficiency ∼90%. Thus, CuO NPs can be used as sustainable, cost-effective and efficient alternative for the removal of toxic industrial effluents from water bodies. [ABSTRACT FROM AUTHOR]

Influence of CuO on the linear/nonlinear optical, elastic, physical features, and radiation protection performance of CuO-based glasses in form (50-y/2)Na2O + (50-y/2)P2O5 + yCuO, (y = 0.0–40 mol%) has been studied in the current article. The density was increased from 2.47 to 3.26 g.cm−3 accomplished with a concurrent decrease in the oxygen molar volume from 13.76 to 12.97 cm3.mol−1 as the mol% of [Cu2+] enhanced in the tested glasses. Also, the Vickers hardness (Hv) was found to increase with increasing CuO content in the current glass systems. The notable tendency of mass attenuation coefficient (MAC) values in the investigated energetic photon range obeyed the sequential order: MACCuI-0 < MACCuI-10 < MACCuI-20 < MACCuI-25 < MACCuI-30 < MACCuI-33 < MACCuI-40. Also, we found that the linear attenuation coefficient (LAC) increased, while the half-value-layer (HVL), and transmission coefficient (TF%) also decreased. The HVL values of the current samples were compared with standard glasses, and it was found to those CuO-based samples possessed a comparable photon protection capacity as RS-360 and RS-520. The linear (nlinear) and nonlinear ( n 2 optical ) refractive index increased from 3.914 to 3.983 and from 2.76 × 10–9 and 3.15 × 10–9. Results uncovered that the optical, radiation protection efficiency and elasto-mechanical characteristics might at the same time be adjusted for an in- or/and out-door scientific and medical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Photo-Fenton-like catalysis allows development of novel advanced oxidation technology with promising application in wastewater treatment. In this work, carbon dots (CDs) were intercalated between CuO nanoparticles and coralloid flower-like graphitic carbon nitride (g-C 3 N 4) to fabricate a ternary CuO/CDs/g-C 3 N 4 hybrid for synergetic visible-light-driven photo-Fenton-like oxidation. The CuO/CDs/g-C 3 N 4 hybrid showed remarkable degradation efficiency towards recalcitrant organic contamination, excellent tolerance to realistic environmental conditions, exceptional stability and wide universality, declaring great potential for practical applications. •OH and •O 2 − radicals were demonstrated to be the primary contributors in the photo-Fenton-like system. Mechanism studies reveal dual charge transfer pathways in the Z-scheme CuO/g-C 3 N 4 heterojunction assisted by interfacial electron transmission bridges of CDs, which can simultaneously boost the reduction of Cu2+ to Cu+ in the Fenton-like cycle and accelerate the Z-scheme electron flow from CuO to g-C 3 N 4 , leading to synergistic enhancement of the catalytic performance. This work would afford a feasible strategy to develop reinforced solar energy-assisted photo-Fenton-like catalysis systems for water remediation. [ABSTRACT FROM AUTHOR]

The interactions of carbon dioxide (CO2) with metal oxides are a significant subject due to the numerous applications in which this reaction is involved. Although this reaction has been extensively studied by various infrared (IR) techniques, only a few (if any) have utilized in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). DRIFTS has an essential advantage over other traditional IR techniques in that it involves minimal sample preparation before analysis. In this work, CO2 adsorption on CoO, CuO, and α‐Fe2O3 nanoparticle surfaces was investigated by using DRIFTS. While the majority of species on CoO and CuO surfaces were observed as carbonate, on α‐Fe2O3 bicarbonate was more prevalent. [ABSTRACT FROM AUTHOR]

Oxidation of Mn(II) or As(III) by molecular oxygen is slow at pH < 9, while they can be catalytically oxidized in the presence of oxide minerals and then removed from contaminated water. However, the reaction mechanisms on simultaneous oxidation of Mn(II) and As(III) on oxide mineral surface and their accompanied removal efficiency remain unclear. This study compared Mn(II) oxidation on four common metal oxides (γ-Al 2 O 3 , CuO, α-Fe 2 O 3 and ZnO) and investigated the simultaneous oxidation and removal of Mn(II) and As(III) through batch experiments and spectroscopic analyses. Among the tested oxides, CuO and α-Fe 2 O 3 possess greater catalytic activity toward Mn(II) oxidation. Oxidation and removal kinetics of Mn(II) and As(III) on CuO indicate that O 2 is the terminal electron acceptor for Mn(II) and As(III) oxidation on CuO, and Mn(II) acts as an electron shuttle to promote As(III) oxidation and removal. The main oxidized product of Mn(II) on CuO is high-valent MnO x species. This newly formed Mn(III) or Mn(IV) phases promote As(III) oxidation on CuO at circumneutral pH 8 and is reduced to Mn(II), which may be then released into solution. This study provides new insights into metal oxide-catalyzed oxidation of pollutants Mn(II) and As(III) and suggests that CuO should be considered as an efficient material to remediate Mn(II) and As(III) contamination. [ABSTRACT FROM AUTHOR]

Hydrothermal technique was used to deposit copper‐oxide (CuO) nanostructures on woven carbon fibers (WCF) to produce a nanostructured interphase that increased the interfacial strength with an epoxy resin matrix. In order to create laminated hybrid composites, CuO‐modified WCF was reinforced with mixture of bisphenol‐A epoxy resin and dimethyl aniline hardener as matrix using the vacuum bagging approach. Enhanced mechanical qualities are the result of increased volume fraction of CuO nanostructures, where the void content is minimal. The mechanical characteristics such as impact strength and tensile strength of CuO‐coated WCF reinforced epoxy resin composite samples were assessed using drop‐down impact test and universal material testing system. The outcomes demonstrate a considerable improvement in impact energy absorption (74.8%), elastic modulus (52%) tensile strength (42%) and in‐plane shear strength (32%) for the CuO‐coated WCF reinforced epoxy resin composites. This work demonstrates that the development of CuO nanostructures can lessen composite delamination and enhance composite performance because of the increase in interfacial surface area between the matrix and the fiber by CuO nanostructures potentially expanding the spectrum of structural applications for these materials. [ABSTRACT FROM AUTHOR]

The hybrid nanocrystals of zinc oxide (ZnO), cadmium oxide (CdO) and copper oxide (CuO) were self-assembled to the nanospheres with special structure in the process of inverse Pickering miniemulsion. The 3-(methacryloxy) propyltrimethoxysilane (MPS) was used to modify the crystalline nanoparticles to obtain the partial hydrophobicity on their surfaces. The influences of the dosage ratio of MPS to the crystalline nanoparticles on the size distribution and surface hydrophobicity of modified nanoparticles were discussed. The modified ZnO, CdO and CuO nanocrystals as solid emulsifiers were self-assembled into four kind structure of nanospheres by inverse Pickering miniemulsion. The dosage usage, the three-phase contact angle and their initial dispersion positions of the modified nanocrystals codetermined the structure of hybrid oxide nanocrystals. The nanospheres of hybrid oxide nanocrystal will be successfully prepared by inverse Pickering miniemulsion; they provide the distinctively photoelectric properties. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles (MONPs) are widely used in agriculture and food development but there is little understanding of how MONPs, including ZnO, CuO, TiO2, and SnO2, impact human health and the environment. Our growth assay revealed that none of these (up to 100 µg/mL) negatively affect viability in the budding yeast, Saccharomyces cerevisiae. In contrast, both human thyroid cancer cells (ML-1) and rat medullary thyroid cancer cells (CA77) displayed a significant reduction in cell viability with the treatment of CuO and ZnO. The production of reactive oxygen species (ROS) in these cell lines, when treated with CuO and ZnO, was found to be not significantly altered. However, levels of apoptosis with ZnO and CuO were increased, which led us to conclude that the decreased cell viability is mainly caused by non-ROS-mediated cell death. Consistently, data from our RNAseq studies identified differentially regulated pathways associated with inflammation, Wnt, and cadherin signaling across both cell lines, ML-1, and CA77, after ZnO or CuO MONP treatment. Results from gene studies further support non-ROS-mediated apoptosis being the main factor behind decreased cell viability. Together, these findings provide unique evidence that the apoptosis in response to treatment of CuO and ZnO in these thyroid cancer cells was not mainly due to oxidative stress, but to the alteration of a range of signal cascades that promotes cell death. [ABSTRACT FROM AUTHOR]