Pure Copper Oxide Research Articles

Use of Camellia sinensis in green synthesis of pure and nickel-doped copper oxide nanoparticles and investigation of their photocatalytic degradation and antibacterial effects

Abstract Green synthesis of metal and metal oxide nanoparticles has been widely studied recently. The cost-effectiveness, as well as the environment-friendly green approach to synthesizing nanoparticles, is a true achievement for the scientific community. In this study, tea (camellia sinensis) leaf extract was used to synthesize pure copper oxide nanoparticles (CuO NPs) and nickel doped copper oxide nanoparticles (Ni/CuO NPs). Synthesized nanoparticles were characterized with UV-visible spectroscopy, PL spectroscopy, PXRD, and FESEM. The optical study of the sample revealed a narrow band gap of 1.60 eV in CuO NPs and 1.98 eV in Ni/CuO NPs. The incorporation of nickel into copper oxide has increased its band gap significantly. FESEM images show a clear picture of spherical shaped CuO and Ni/CuO NPs. PXRD shows that both samples have fine crystalline structure. The photocatalytic degradation effects were tested using methylene blue (MB) dye in the presence of sunlight. Moreover, the antibacterial activities of the samples showed remarkable results against Gram-positive Staphylococcus aureus (S. aureus) bacteria. It is found that the nickel-doped CuO NPs are more effective in photocatalytic degradation and antibacterial activities than pure CuO NPs.

Advancements in CuO nanoparticle technology: synthesis, characterization of copper oxide nanoflowers

Abstract Nanostructured materials, including metal and metal oxide nanoparticles, play a crucial role in advancing diverse scientific and technological areas. Transition metal oxides such as CuO are integral to developments in fields like antibacterial treatments, solar energy conversion, sensing technologies, catalysis, magnetic storage, supercapacitors, and semiconductor devices. This research is centered on the hydrothermal synthesis of pure copper oxide nanoflowers, which are noted for their extensive surface areas. Zeta potential analysis, ultraviolet-visible spectrophotometry, field-emission scanning electron microscopy, and Fourier-transform infrared spectroscopy were some of the methods utilized to characterize these nanoparticles. The results showed that band gap energies, crystallite size, and lattice characteristics are all greatly affected by CuO. XRD results indicated a covellite monoclinic polycrystalline structure predominantly orientation with average crystallite sizes around 15.84 nm. FE-SEM imagery depicted the hierarchical, cauliflower-like structure of the CuO nanoparticles. Optical assessments revealed band gap values ranging from 2.58 eV. The findings underscore the broad potential of CuO nanoflowers across various technological applications.

Study of the structural and optical properties of pure copper oxide and doped with zinc at fixed weight percentages

Through this research, the effect of doping with zinc ions on the structural and optical properties of copper oxide particles doped with zinc at certain weight percentages was study using Radiofrequency plasma deposition technology. X-ray diffraction (XRD) analyses and field emission scanning electron microscopy were used to ascertain the materials' characteristics. Ultraviolet and visible spectroscopy of pure and doped thin films was also perform to calculate the band gap and electrical conductivity It was discovered using the XRD readings that the pure copper particles saturated with zinc had a crystalline size. It changes as Zn concentration rises and is influenced by the CuO lattice's strain and dislocation density. The thin film samples have structures resembling irregular and cubic grains, as demonstrated by the FE-SEM pictures. After doping with Zn, their homogeneity increases and adopts a regular granular nature. The band gap was also calculated for pure CuO particles as well as those doped with certain percentages of Zn. It was note that the addition of Zn worked to reduce Band gap for CuO

Synthesis of CuO/NiO nanostructured hybrid electrode for supercapacitors

Supercapacitors employing copper metal oxides have garnered significant interest due to their substantial theoretical capacity and expansive active surface area. However, the performance of pure copper oxide electrode materials cannot meet the high demands currently placed on supercapacitors. In this study, a convenient, efficient, two-step electrodeposition method was utilized to develop micro/nanostructures of CuO/NiO on nickel foam. The synthetic strategy optimizes the capacitive performance of the composite by adjusting the deposition parameters during the growth of the NiO film.The CuO/NiO electrode can provide an area ratio capacitance of up to 1435.62 mF/cm2, the addition of NiO improves the area capacitance of the electrode material and the capacitance retention after cycling. In addition, the CuO/NiO composite material has been used to prepare solid-state symmetric supercapacitors, the device can reach a maximum energy and power density of 31.89 μWh/cm2 and 2099.76 μW/cm2, respectively. These results suggest that CuO/NiO electrodes exhibit promising potential as energy storage electrode materials.

Evaluation of structural parameters of monoclinic nanocrystalline CuO and study of sunlight-driven photocatalytic dye degradation, antimicrobial and antioxidant potential

Highly pure, crystalline and spherical-shaped Copper oxide nanoparticles (NPs) have been synthesized via facile chemical coprecipitation. Various models including the Scherrer, Monshi-Scherrer, Williamson-Hall, Size-Strain Plot and Halder-Wagner method have been applied to study the crystal structure characteristics. The lattice parameters associated with the monoclinic crystal lattice of CuO NPs were estimated to be a = 4.69 Å, b = 3.41 Å, c = 5.14 Å and β = 99.87(degree), unit cell volume V = 81.35Å3 and cell density dx = 6.49 g/cm3. The photocatalytic dye degradation proficiency at 20 mg/l CuO concentration and 120 min sunlight exposure results the order of percentage dye degradation Malachite Green (88.4%) > Crystal Violet (70.8%) > Eosin Yellow (70.2%) > Methylene Blue (54.08%) dyes. The antimicrobial activity assessment was done against the broad-spectrum pathogenic microbes unveiled the exceptional microbial controlling capability of CuO NPs. Furthermore, the antioxidant activity test demonstrated the potential free radical scavenging activity of CuO NPs with an IC50 value of 47.733 µg/ml. Highlights Synthesis of pure and spherical shaped nanocrystalline CuO was done by using low cost and facile chemical coprecipitation method. XRD, FTIR, FESEM, EDX, UV-Vis, and Raman spectroscopic techniques were used for characterization purpose. The structural and crystallographic parameters of monoclinic crystal structure of CuO NPs were evaluated successfully. The photocatalytic performance of CuO NPs follow the percentage dye degradation order as MG (88.4%) > CV (70.8%) > EY (70.20%) > MB (54.08%) after 120 minutes of sunlight exposure. CuO NPs exhibit promising antifungal activity against COVID-19 associated Pulmonary Aspergillosis (CAPA) causing pathogenic fung. CuO NPs show potential DPPH free radical scavenging activity with an IC50 value of 47.733 µg/ml.

Study on the Optical and Gas-Sensing Performance of Zn-doped CuO Films

The pure copper oxide thin film was deposited on glass substrates by SILAR method with 30 cycles. To examine the doping effect, Zn-doped films at different doping ratios were prepared under the same conditions as the undoped film. The XRD, SEM and Raman measurements were performed to investigate the morphological and structural properties of the samples. Analysis showed increasing aggregation and amorphous structure with doping. The optical parameters were characterized by spectrophotometer measurement and relevant formulas. The band gap energies were determined to increase from 2.50 to 2.79 eV with the increasing Zn rate. The Hervé and Vandamme, Moss and Ravindra relations were used to determine the refractive index. The room temperature gas-sensing performance for the undoped and doped samples were reported and the responses for 5 ppm gas were calculated as 249 %, 800 %, 189 % and 15 % for the CuO, 1Zn:CuO, 3Zn:CuO and 5Zn:CuO, respectively. The response of CuO thin films changed with doping, and 1% Zn doping rate was determined as the optimal rate in this study.

Excited state absorption induced optical limiting behavior of pure, single, and co-doped copper oxide nanoparticles

Underneath nano pulsed green laser (Nd: YAG), nonlinear absorption and optical limiting behavior were analyzed using Z-scan technique for pure CuO, Ag, and Mn-doped CuO (single dopant), and Ag/Mn-doped CuO (co-dopant) nanoparticles intermediated from M. Oleifera leaf extract. X-ray diffraction pattern confirmed that the synthesized nanoparticles were in good crystalline nature with a monoclinic phase and the average crystallite size was estimated in the range of nanometer. FE-SEM analysis displayed that the pure CuO, Ag-doped CuO, and Ag/Mn-doped CuO appear as nanospheres whereas Mn-doped CuO forms themselves as nanorods. The existence of Cu, O, Ag, and Mn elements in synthesized nanoparticles was affirmed by an EDAX spectrum. FT-IR analysis confirms the presence of functional groups. In zeta potential analysis the negative (-ve) potential values −34.23 mV to −34.80 mV indicate the stability of the nanoparticles. The optical study revealed that the nanoparticles possess absorbance maxima in the UV region between 260 nm to 294 nm. The occurrence of a single ionized oxygen vacancy defect was affirmed by the photoluminescence studies. Z-scan studies with nano pulsed Nd: YAG lasers show all the samples exhibit two-photon absorption (2 PA) and optical limiting behavior. In contrast with pure and co-dopant materials (Ag/Mn-doped CuO), the dominant nonlinear absorption coefficients (0.90 × 10−10 m/W, & 0.98 × 10−10 m/W) and submissive values of optical limiting threshold (1.69 × 1012 W/m2 & 1.31 × 1012 W/m2) were found for single dopant materials (Ag & Mn-doped CuO). Thus single metal doped CuO finds potential application in the creation of laser safety devices against massive power nano pulsed green laser beams.

Innovative approach to synthesize Mo-Doped CuO Nanostructures: Uncovering structural and photocatalytic insights

The synthesis of molybdenum-doped copper oxide was carried out using a sol–gel technique, with sodium hydroxide as a pH regulator. Structural, morphological, and compositional analysis of both pure and molybdenum-doped copper oxide was observed through X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). For the monoclinic CuO nanostructure, key structural parameters like crystallite size, lattice parameters, micro strain, and dislocation density from XRD data was determined. Several methods, were employed to assess the crystallite size, micro strain, and dislocation density of synthesized nanostructures. The photocatalytic activity of Mo-doped CuO nano photocatalyst was evaluated using PL spectroscopy. Notably, the results demonstrated that 3% molybdenum-doped copper oxide removed 91% of the MB dye, outperforming the pure CuO sample, which only achieved 59% removal. This enhanced performance can be attributed to the increased surface area and optimized band gap of the Mo-doped CuO. The tuned band gap and unique nano architecture of the doped CuO not only facilitated the excitation process but also facilitated in transporting photo-induced species to the photo catalyst’s surface. These findings highlight the exceptional photocatalytic efficacy of the 3% molybdenum-doped CuO photo catalyst, showcasing its potential for treating toxic industrial effluents even through multiple cycles.

Oxidation dynamics of Cu thin film on Si surface by mass analyzed O+ ion implantation and study their electrical and optical properties

In this article, the ion beam-induced oxidation dynamics of copper (Cu) thin film and transport properties of the ion-modified films, deposited on Si substrate by e-beam evaporation, are investigated. Low energy (10 keV) O+ ion bombardment on Cu films at normal incidence leads to the formation of cuprous oxide (Cu2O) and cupric oxide (CuO) phases at different stages of bombardment. The dynamical change of the cuprous oxide (Cu2O) phase to the mixture of Cu2O and CuO phases with increasing ion fluence is observed via X-ray photoelectron spectroscopy (XPS) and grazing incidence X-ray diffraction. Ion implantation leads to a decrease in crystalline size with an increase in ion fluence. The increase of oxygen concentration and the absence of foreign impurities in Cu films at higher ion fluence are also measured by XPS and Energy-Dispersive X-ray spectroscopy. The oxygen concentration reduces from 82 % to 58 % for the cuprous oxide phase, whereas the same increases from 18 % to 42 % for the cupric oxide phase. The optical response due to enhancement of the oxygen atoms in ion-modified Cu thin films investigated using UV–visible spectrophotometer, shows higher absorption in the visible region compared to untreated Cu film. Post-bombardment changes in resistivity of copper oxide films, containing the mixture of two chemical phases, exhibit metallic and semiconducting behavior at temperatures 10–110 K and above 110 K, respectively. Temperature varying (300–350 K) Hall measurements of the oxygen implanted Cu film shows changes in the threshold values of mobility (1.4 to 2.4 cm2/Vs), resistivity (18 × 10−6 -150 × 10−6 Ω-cm) and carrier concentration (2 × 1022 -15 × 1022 cm−3). The potential applications of pure copper oxide films prepared by low-energy ion implantation without thermal treatment are also addressed here.

Optical and thermal characterization of pure CuO and Zn/CuO using laser-induced breakdown spectroscopy (LIBS), x-ray fluorescence (XRF), and ultraviolet–visible (UV–Vis) spectroscopy techniques

We present elemental analysis and thermal characterization of pure and two different concentrations of zinc-doped copper oxide (CuO) samples using different analytical techniques. The quantitative as well as qualitative investigations, were performed by incorporating calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique. The plasma was generated on the samples surface by focusing a first harmonic of Nd: YAG laser of 1064 nm wavelength and the time-integrated emission spectra was achieved through a set of five spectrometers equipped with a charge-coupled-device. The acquired optical emission spectra from laser-generated plasma show different concentrations of zinc and copper in different samples which are consistent with their percentage composition measured during the sample synthesis. Using LIBS emission analytical lines, the Boltzmann technique was utilized for estimating the excitation temperature, while the number density was evaluated using the well-known Stark broadening line profile method. Besides, the CF-LIBS elemental analysis was validated by the x-ray fluorescence technique. For the optical study, ultraviolet–visible spectroscopical analysis was performed to find the bandgap of pure and zinc-doped copper oxide samples and consequently, variation in bandgap was studied with the growth of zinc doping. In addition, the thermal properties of the samples were analyzed using the beam deflection spectroscopy technique. The results shows that thermal diffusivity () and thermal conductivity (), increased with an increase in zinc concentration.

Photocatalytic and antibacterial properties of pure and niobium-doped copper oxide nanoparticles

Photocatalytic and antibacterial properties of pure and niobium-doped copper oxide nanoparticles

Hydrothermal-assisted synthesis and characterization of MWCNT/copper oxide nanocomposite for the photodegradation of methyl orange under direct sunlight

In this study, we report synthesis of a novel MWCNT/copper oxide hybrid nanocomposite and pristine copper oxide using hydrothermal techniques and employed them as a sunlight-driven photocatalyst for the degradation of methyl orange organic (MO) pollutant. The prepared specimens were evaluated using various characterization techniques to analyze the crystallographic, optical, and nanoscale characteristics and the results revealed that the incorporation of MWCNTs significantly altered the crystalline phase, lattice parameters, particle size, shape, and optical band gap when compared with pure copper oxide sample. Pure copper oxide, MWCNT/copper oxide nanocomposite and MWCNT exhibited band gaps of 1.43 eV, 1.90 eV, and 3.8 eV, respectively. After 6 h of exposure to sunlight, pure copper oxide and MWCNT/copper oxide hybrid nanocomposite photodegraded 85 % and 92 % of the MO dye, with pseudo-first-order kinetics and high recyclability up to 5 cycles. The proposed composite shows higher solar radiation-induced photodegradation than pure copper oxide owing to its hybrid heterostructure, making it a promising photocatalyst for wastewater treatment.

Highly Selective Electrochemical CO2 Reduction to C2 Products on a g-C3N4-Supported Copper-Based Catalyst.

Herein, a novel approach used to enhance the conversion of electrochemical CO2 reduction (CO2R), as well as the capacity to produce C2 products, is reported. A copper oxide catalyst supported by graphite phase carbon nitride (CuO/g-C3N4) was prepared using a one-step hydrothermal method and exhibited a better performance than pure copper oxide nanosheets (CuO NSs) and spherical copper oxide particles (CuO SPs). The Faradaic efficiency reached 64.7% for all the C2 products, specifically 37.0% for C2H4, with a good durability at -1.0 V vs. RHE. The results suggest that the interaction between CuO and the two-dimensional g-C3N4 planes promoted CO2 adsorption, its activation and C-C coupling. This work offers a practical method that can be used to enhance the activity of electrochemical CO2R and the selectivity of C2 products through synergistic effects.

Investigating the influence of Ni doping on the CuO thin films deposited via ultrasonic spray pyrolysis: Structural, optical and H2 gas sensing analyses

Pure and nickel doped copper oxide thin films were successfully grown on a soda lime glass substrates including various amounts (1, 2, 4, and 8%) of nickel dopants via ultrasonic spray pyrolysis method. The effects of the different impurity doping concentrations on the structural, morphological, optical, and H2 gas sensing properties of the prepared samples were assessed by performing X-ray Diffraction, scanning electron microscopy, ultraviolet–visible spectroscopy, photoluminescence spectroscopy, gas sensing measurements, and X-ray photoelectron spectroscopy. The structural observations revealed that the grown films have polycrystalline nature with monoclinic cubic crystal structure of copper oxide with no secondary phases present, and grain sizes increased in general as the doping percentage increased except for the 4% nickel doped sample. The morphological analysis showed that the impurities clearly led to modifications in the shapes of the grown copper oxide nanocrystals. In the optical measurements, it was uncovered that the ideal impurity level can enhance the absorbance features of the copper oxide material, and a slight increase in bandgap occurred due to the first level of impurity doping, but then the bandgap decreased as the impurity contents increased. A gradual decrease in the intensity of luminescent emissions was observed in the photoluminescence spectra as the doping concentration increased, which may be associated with the defects caused by the added nickel ions into the copper oxide lattices. Gas sensor measurements disclosed that the produced films were responsive when exposed to H2 gas, and enhanced responsivity was realized by the nickel doping compared to that of pure copper oxide sample. X-ray photoelectron spectroscopy confirmed the presence of aimed chemical compositions in the prepared thin films.

Dimethyl Ether Oxidation over Copper Ferrite Catalysts

The depletion of fossil energy sources and the legislation regarding emission control demand the use of alternative fuels and rapid progression of aftertreatment technologies. The study of dimethyl ether (DME) catalytic oxidation is important in this respect, as DME is a promising clean fuel and at the same time a VOC pollutant present in the tail gases of industrial processes. In the present work, copper ferrite catalysts synthesized via the citrate complexation method have been evaluated in DME oxidation. N2-physisorption, XRD, H2-TPR, and XPS were employed for the characterization of the mixed oxide catalysts. The copper ferrite spinel phase was detected in all samples accompanied by a gradual decrease in the bulk CuO phase upon increase in iron content, with the latter never vanishing completely. The Fe0.67Cu0.33 catalyst exhibited the highest catalytic activity in DME oxidation, attaining approximately a 4-fold higher oxidation rate compared to the respective pure copper and iron oxides. The enhanced catalytic performance was attributed to the higher specific surface area of the catalyst and its enhanced redox properties. Highly dispersed copper species were developed owing to the formation of the spinel phase. DME-TPD/TPSR experiments showed that the surface lattice oxygen of the Fe0.67Cu0.33 catalyst can oxidize preadsorbed DME at a lower temperature than all other catalysts which is in agreement with the H2-TPR findings.

Synthesis of Green and Pure Copper Oxide Nanoparticles Using Millettia Pinnata Leaf Extract and Their Characterisation

Copper oxide nanoparticles (CuO Nps) were synthesized using Millettia pinnata leaf extract via an eco-friendly, cost-effective, reliable, and simple green synthetic pathway and were evaluated for visible light assisted photocatalytic properties by carrying out photocatalytic degradation of dyes. The green synthesized CuO NPs were characterized using various analytical techniques like UV-Visible Spectroscopy (UV-Vis), Fourier-Transform Infrared Spectroscopy (FT-IR), X-Ray Diffractometer (XRD), Transmission Electron Microscopy (TEM) and (EDAX) analysis. The biosynthesis was affirmed by UV-vis spectroscopy exhibiting peak at 290 nm. In FTIR analysis, the chemical bonds corresponds to the phytochemicals responsible for bioreduction activity were identified. Energy dispersive spectroscopy (EDS) showed high intense metallic peak of copper (Cu), oxygen (O) and low intense peaks of carbon (C) due to the capping action of biomolecules of plant extract in CuO NPs formation. The X-ray diffraction (XRD) pattern showed distinctive peaks corresponding to (200), (211) and (310) planes revealing the high crystalline nature of synthesized CuO NPs. The TEM analysis also confirmed that the formed nanoparticles had spherical morphology with uniform symmetry.

Acacia nilotica Pods' Extract Assisted-Hydrothermal Synthesis and Characterization of ZnO-CuO Nanocomposites.

This work represents a novel combination between Acacia nilotica pods’ extract and the hydrothermal method to prepare nanoparticles of pure zinc oxide and pure copper oxide and nanocomposites of both oxides in different ratios. Five samples were prepared with different ratios of zinc oxide and copper oxide; 100% ZnO (ZC0), 75% ZnO: 25% CuO (ZC25), 50% ZnO: 50% CuO (ZC50), 25% ZnO: 75% CuO (ZC75), and 100% CuO (ZC100). Several techniques have been applied to characterize the prepared powders as FTIR, XRD, SEM, and TEM. The XRD results confirm the formation of the hexagonal wurtzite phase of zinc oxide and the monoclinic tenorite phase of copper oxide. The microscopy results show the formation of a heterostructure of nanocomposites with an average particle size of 13–27 nm.

Green Synthesis of Pure and Silver Doped Copper Oxide Nanoparticles using Moringa Oleifera Leaf Extract

With the intense development of nanotechnology, copper oxide nanoparticles have terrible immense applications in electrical, optical and Bio-medical applications. To safeguard the environment and to mortify the toxicity in chemicals, the present work was carried out for synthesizing Pure and Silver (Ag) doped Copper Oxide (CuO) nanoparticles of different concentrations using Moringa Oleifera leaf extract and it shows a good result towards antimicrobial agents. These green synthesized nanoparticles were subjected to characterization techniques, X- ray Diffraction (XRD), Scanning Electron Microscopy (SEM) with Energy Dispersive X- ray Analysis (EDAX), Fourier Transform Infrared spectroscopy (FTIR) and Ultraviolet–Visible spectroscopy (UV). From XRD, the average crystallite size for pure and silver doped copper oxide nanoparticles was found to be in the nanometer range and it belongs to a monoclinic structure. The surface morphology and the elemental compositions of nanoparticles were confirmed by SEM with EDAX. Functional groups were observed by FTIR spectra. From the optical absorption spectrum, the bandgap for pure copper oxide was found to be 1.2 eV, while increasing the dopant concentrations shows enhancing results towards optical properties.

Influence of aluminum ion on the structural, optical, and electrical properties of CuO thin films for the PN-Junction diode application

Pure and (1, 3, and 5 wt%) Aluminum-doped copper oxide(Al:CuO) thin films were prepared using the JNS spray-pyrolysis technique using analytical grade copper chloride and aluminum chloride as a precursor. The monoclinic structure of the CuO film has been confirmed by an X-ray diffraction (XRD) study. The microstructure of the films is analyzed with the help of a scanning electron microscope (SEM). The optical characteristics of the grown films have been examined with the help of UV–vis spectroscopy, from which the bandgap of the materials of the coated films are calculated. Electrical properties such as conductivity and the diode activity of the films are studied using I-V characterization, which shows the improved electrical conductivity with the increase in doping concentration. Diodes are fabricated using pure and Aluminum-doped p-type CuO thin films coated on the n-type silica wafer by the JNS technique, and the rectification behavior is found to improved at a higher doping concentration of Al3+ ions.

Influence of Zinc Doping on the Structural, Morphological, Optical and Electrical Properties of Copper Oxide Thin Films Prepared by Jet-Nebulizer Spray Pyrolysis Technique

This research details the deposition and characterization of adding zinc (Zn) impurities with different doping concentrations (1%, 3%, and 5%) into copper oxide (CuO:Zn) by using a jet nebulizer spray pyrolysis system. The impact of zinc doping on the different copper oxide properties was investigated. The structural studies confirm that pure copper oxide and zinc doped copper oxide thin films are matched with monoclinic structure. High resolution schottky field emission scanning electron microscopy and Energy dispersive spectrum analysis identifies the surface structure and chemical composition of pure CuO and CuO: Zn thin films. EDS spectra reveal the occupancy of Cu, O, and Zn elements in the pure CuO and CuO:Zn thin films. The highest transmittance was observed as 66.91% for 5% Zn concentration. The absorption studies clearly indicated that the absorbance of the films was decreased when Zn doping concentration increase. The energy band gap value (Eg) is calculated as 2.01eV for pure CuO and the value of Eg for CuO:Zn thin films are varied from 2.07 to 2.26 eV. Keithley high resistance and low current electrometer was used to measure direct current conductivity of both pure CuO and CuO: Zn thin films and maximum conductivity value was observed for CuO: Zn (5%) thin film.