Synthesis Of CuO Nanoparticles Research Articles

Biogenic synthesis of porous CuO nanoparticles: Synergistic effects in photocatalytic dye degradation and electrochemical energy storage applications

This study explores the biogenic synthesis of CuO nanoparticles functionalized with Solanum nigrum, using Acalypha indica leaf extract as a reducing agent. The biogenically synthesized CuO nanoparticles were comprehensively characterized by various analytical techniques, involves X-ray diffraction analysis (XRD), BET surface area analysis (BET), energy-dispersive X-ray spectroscopy (EDAX), X-ray photoelectron spectroscopy (XPS), UV–Visible spectral analysis (UV), Fourier transform infrared spectroscopy (FTIR), fluorescence spectroscopy, photocatalytic degradation, antimicrobial assay, cytotoxicity assay, electrochemical analysis, and linear sweep voltammetry studies. The XRD analysis revealed end centered monoclinic phase with a 10 nm average crystalline size. BET analysis showed a mesoporous structure with a surface area of 11.54 m2/g. XPS and EDAX confirmed the presence of Cu2+ and O2− ions. SEM and TEM images indicated spherical, and porous nanostructures. UV–Visible spectroscopy identified an active optical range of 508–518 nm (2.40–2.45 eV), suggesting potential photocatalytic activity. The photocatalytic degradation efficiencies of Methylene blue (98.8 %) and Rhodamine B (95 %) were achieved after 100 min of irradiation. Antimicrobial tests demonstrated effectiveness against Staph. aureus, E. coli, Shigella flexneri, and Candida tropicalis. The nanoparticles exhibited notable cytotoxicity against colorectal cancer cells with IC50 values of 58.66 μg/ml and 66.78 μg/ml. Additionally, a symmetric supercapacitor electrode using these nanoparticles achieved a specific capacitance of 375 Fg−1 at the current density of 1 Ag−1. This research underscores the versatile applications of biogenic CuO nanoparticles in photocatalysis, antimicrobial treatments, cancer therapy, and energy storage.

Versatile performance of hydrophilic PVDF/CuO nanocomposite membranes for TDS removal in RO reject

ABSTRACT In the current study, by using the phase inversion process, PVDF/CuO nanocompositmembranes with diversified concentrations of copper oxide (CuO) nanoparticles were fabricated to reduce the TDS in RO reject. Consequently, compared to pure PVDF membrane, the hydrophilicity of PVDF membrane bearing 2 wt% of chemically synthesized CuO nanoparticles is higher. This was justified through the contact angle which diminished from 110.9° to 58.2°. The improved hydrophilicity, porosity, and pore size are the vital drivers for the fabricated nanocomposite membranes to exhibit an 81% surge in pure water flux and a 75% rise in permeate flux. Fouling of PVDF/CuO nanocomposite membranes was mitigated by incorporating CuO nanoparticles, decreasing the surface roughness. The antifouling capabilities of the fabricated nanocomposite membranes are enhanced by a higher flux recovery ratio of 97.28. Additionally, the outcomes demonstrated that the nanocomposite membrane performs better in TDS removal, with 89% efficiency in RO reject. Thus, the PVDF/CuO nanocomposite membrane has great prospects in applications necessitating the filtration process.

CuO nanoparticles: green combustion synthesis, applications to antioxidant, photocatalytic and sensor studies.

The use of metal oxide nanoparticles for heterogeneous photodegradation is a prominent method for the removal of organic dyes from water resources. Compared to conventional approaches to treat polluted water, it is a more preferable method because of its environmental friendliness, low cost, and no requirement of extreme temperature and pressure. Among all the nanoparticles, CuO is a prominent material. Therefore, this study reports on the biogenic preparation of CuO nanoparticles by adopting a combustion method and Samanea saman pod extract as fuel. The synthesized nanoparticles were characterized through X-ray diffraction spectroscopy to confirm the crystallinity of CuO; the surface morphology of the material was studied using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) and the purity of the material was confirmed by energy dispersive X-ray spectroscopy. The degradation efficiency of CuO nanoparticles towards methylene blue dye, a model pollutant present in water resources, was assessed and found to be 97% after 90 minutes of light exposure. The synthesized CuO nanoparticles were also examined for antioxidant and electrochemical sensing studies using cyclic voltammetry. Results showed that CuO nanoparticles function as a strong antioxidant and are a very effective electrochemical sensor.

Cu(II) Biosorption and Synthesis of CuO Nanoparticles by Staphylococcus epidermidis CECT 4183: Evaluation of the Biocidal Effect

Copper contamination of natural waters is a global problem that affects ecosystems and public health, yet this metal is an essential micronutrient and has important applications. The efficacy of Staphylococcus epidermidis CECT 4183 as a Cu(II) biosorbent in synthetic solutions and its potential ability to synthesize CuO nanoparticles (CuO-NPs) from its cellular extract was investigated. In addition, the biocidal potential of the nanoparticles was evaluated against five microorganisms. Using response surface methodology, the optimal operating conditions were determined to be biomass dose, 0.2 g/L, and pH 5.5. Equilibrium tests were performed, and biosorption isotherms were obtained for four models with a maximum biosorption capacity of 48.14 mg/g for the Langmuir model. Different spectroscopic and microscopic techniques were used to determine the mechanisms involved in the biosorption process, which was dominated by surface physicochemical interactions with strong involvement of methyl, methylene, carbonyl, amino, and phosphate groups. The techniques also allowed for characterizing the obtained nanoparticles, which had a quasi-spherical morphology and an average size of 14 nm. Finally, biocidal tests showed that the CuO-NPs had a good inhibitory capacity for the microorganisms tested, with minimum inhibitory concentrations (MIC) between 62.5 and 500 µg/mL for bacteria and between 1000 and 2000 µg/mL for yeasts. S. epidermidis CECT 4183 showed good potential for Cu(II) bioremediation and for the synthesis of CuO-NPs with biocidal capacity. S. epidermidis CECT 4183 showed good potential for use in Cu(II) biosorption, and its cell extract presented a high capacity for the green synthesis of CuO-NPs, which at the same time turned out to be good biocidal agents.

A comparative study of in vivo toxicity in zebrafish embryos synthesized CuO nanoparticles characterized from Salacia reticulata.

The Salacia reticulata, a medicinal woody climbing shrub, was utilized for our study, the green synthesis of CuO nanoparticles, which were analyzed through SEM, EDX, FTIR, XRD, and UV‒Vis spectroscopy. This study assessed the toxicity to zebrafish embryos and explored the antibacterial, cytotoxic, antidiabetic, and anti-inflammatory properties of the synthesized nanoparticles. In results, the UV absorption of the CuO NPs showed that the intensity of nanoparticle green colloidal suspension changed from blue to green, which also confirmed that the spectrum of the green CuO NPs changed from colorless to black. in FT-IR and XRD spectral analysis to identify functional groups and determine the particle size of CuO NPs prepared by green and chemical methods. Its showed that CuO NPs (green) had a size of approximately 42.2nm, while CuO NPs (chemical) had a size of approximately 84nm. The morphology of these NPs was analyzed using SEM-EDX. Compared with their chemically prepared counterparts, the green-synthesized CuO nanoparticles demonstrated superior dispersion. Additionally, both green and chemical CuO nanoparticles at a concentration of 200 µL/mL caused developmental anomalies and increased mortality in zebrafish embryos and larvae. The green and chemical CuO NPs inhibited α-glucosidase enzyme activity at concentrations between 10 and 50 µL/mL, with IC50 values of 22 µL/mL and 26 µL/mL, respectively. The extract exhibited anti-inflammatory activity, with IC50 values of 274 and 109 µL/mL. The authors concluded that this green nanoparticle method has potential as a more eco-friendly and cost-effective alternative to traditional synthetic methods. NPs are widely used in human contact fields (medicine and agriculture), hence synthesis methods that do not involve toxic substances are becoming increasingly important.

Combustion enhancement and emission reduction in RCCI engine using green synthesized CuO nanoparticles with Cymbopogon martinii methyl ester and phytol blends

Cymbopogon martini, also known as Palmarosa, is a grass species in the Cymbopogon genus, native to India and widely cultivated in tropical regions for oil production. Phytol, a constituent of chlorophyll, has garnered attention in the biofuels industry due to its potential for conversion into biodiesel through transesterification. Its abundance and renewable nature underscore its relevance for sustainable development. This study investigates the energy potential of waste Cymbopogon martinii Methyl Ester (CMME) in engine combustion systems using reactivity-controlled compression ignition (RCCI) in a single-cylinder, four-stroke diesel engine for low-temperature combustion. The process involves blending low-reactivity fuel (LRF), such as phytol (Acyclic diterpene alcohol and a constituent of chlorophyll), with high-reactivity fuel (HRF), namely CMME, in carefully monitored proportions. CMME25 is used as the primary fuel, supplemented with varying amounts of phytol (10 %, 20 %, and 30 %). Heat release rate (HRR) analysis indicates that phytol improves combustion efficiency up to a 20 % blend in RCCI mode. However, exceeding a 30 % phytol blend reduces brake thermal efficiency (BTE). RCCI mode also shows decreased nitrogen oxide and smoke emissions but increased hydrocarbon (HC) and carbon monoxide (CO) emissions. Improved homogeneity and ignition delay result in higher peak pressure and HRR compared to traditional methods. Further investigation focuses on the effects of CuO nanoparticles on a CMME25 and PHY20 % blend in RCCI mode. CuO nanoparticles (50–100 ppm) enhance brake thermal efficiency, improve combustion parameters (ignition delay, HRR, and cylinder pressure), and reduce emissions. The study concludes that a blend of CMME25+PHY20 % with 100 ppm CuO in RCCI mode is a promising alternative to traditional diesel fuel, offering a sustainable and efficient energy solution.

Terminalia catappa leaf extract as a bio-reducing agent to synthesize Cu2O nanoparticles for methylene blue photodegradation

The large tree species Terminalia catappa is a member of the Combretaceae family and is mainly found in tropical climates. They are commonly cultivated for shade because they have huge, dense foliage. Numerous polyphenols, including flavonoids, tannins, saponins, and phytosterols, are present in the leaves. In this study, the green chemical method was used to extract polyphenols from dried green almond leaves. They were employed in the synthesis of Cu2O nanoparticles as a reducing agent. FTIR and UV–Vis were used to describe the leaf extract of Terminalia catappa after the chlorophyll was removed. Copper salt was used to create Cu2O nanoparticles via a reduction process. The extract's potential for photocatalytic dye degradation has also been explored. The obtained Cu2O had a spherical shape with dimensions of 50–100 nm, and its band gap energy reached 1.945 eV to remove methylene blue from aqueous media under visible light irradiation conditions. At an initial MB concentration of 10 ppm, the decomposition efficiency reached 71.99% after only 2 h of exposure to simulated sunlight. The decomposition process occurred according to a pseudo-first-order kinetic model with a rate constant of 0.0084 min−1.

Improving the in-situ upgrading of extra heavy oil using metal-based oil-soluble catalysts through oxidation process for enhanced oil recovery

The demand for fuel from unconventional sources is increasing all over the world, however, there are still special and strict regulations regarding the methods of enhanced oil recovery as well as the content of the oil produced, including the amount of sulfur. In-situ combustion (ISC) is an attractive thermal method to enhance oil recovery and in-situ upgrading process. In this work, copper (II) oleate and copper (II) stearate were used for the oxidation of extra heavy oil with high sulfur content in the ISC process using a self-designed porous medium thermo-effect cell (PMTEC) and visual combustion tube. Using PMTEC the catalytic performances of the synthesized oil-soluble copper (II) oleate and copper (II) stearate and kinetic parameters such as activation energy using Ozawa-Flynn-Wall method were studied. The X-ray diffraction (XRD) and high-resolution field emission scanning electron microscopy were used to examine the characteristics of in-situ synthesized CuO nanoparticles during oxidation. As shown, the presence of oil-soluble copper (II) stearate and copper (II) oleate reduced oil viscosity from 9964 to 8000 and 6090 mPa˙s, respectively. Following ISC process in porous media in the presence of copper (II) oleate, the high sulfur extra heavy oil upgraded, and its sulfur content decreased from 10.33 to 6.79%. Additionally, SARA analysis revealed that asphaltene and resin content decreased in the presence of oil-soluble catalysts. During the oxidation reaction, homogeneous catalyst decomposed into nanoparticles, and heterogeneous catalyst is distributed uniformly in porous media and played an active role in the catalytic process. It should be noticed that, these kind of oil-soluble catalysts can be novel and highly potential candidates for initiation and oxidation of extra heavy oil in order to decrease the viscosity, enhanced oil recovery and production of the upgraded oil.Graphical abstract

Development of CuO nanoparticles modified electrochemical sensor for detection of salbutamol

Abstract Metal oxide structures are being utilized in an increasing variety of applications. This study used cyclic and differential pulse voltammetry techniques to investigate the possible utilization of copper oxide (CuO) nanoparticles modified carbon paste electrode (CPE) for the redox reactions of salbutamol (SAL). The electrochemical performance of the SAL analyte in a complex matrix environment in Ventolin was evaluated in order to assess the appropriateness of the proposed sensor in a real sample environment. CuO nanoparticles were produced via a straightforward, cost-effective and efficient sol–gel method, and characterization studies of synthesized CuO nanoparticles were performed by scanning electron microscopy, x-ray Diffraction (XRD), and x-ray photoelectron spectroscopy. The synthesized CuO nanoparticles had a spherical shape and particle size was found to be 74 nm. The crystal size of the CuO particles was calculated to be 21.79 nm using the Debye–Scherrer equation. Under optimal conditions, differential pulse voltammetry demonstrated a linear response in the 50 nM to 100 μM range, with a salbutamol detection limit of 50 nM (S/N = 3). The SAL concentration (R 2 = 0.9971) was found to have a good correlation coefficient. The reproducibility of the biosensor was investigated and evaluated with a relative standard deviation of 3% (n = 8). The storage stability of CuO modified CPE for two weeks was evaluated based on the response of DP current measured at intervals every two days. According to the measurement results, the modified electrode exhibited good stability and reproducibility while maintaining 80% of its stability. It is also a rapid and dependable sensor candidate with a measurement time of approximately 20 s. The developed electrode has been utilized successfully to determine doping material with improved performance.

Vacancy induced enhanced photocatalytic activity of nitrogen doped CuO NPs synthesized by Co-precipitation method

The chemical co-precipitation method, an effective approach in the synthesis of nanomaterials, was used to synthesize CuO nanoparticles (NPs). Structural and morphological modification of undoped and nitrogen (N) doped CuO nanoparticles were studied thoroughly using X-ray diffraction (XRD), FT-IR and field emission scanning electron microscope (FE SEM). Doping effect on defects was investigated using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and photoluminescence (PL) spectroscopy. Thus, the effect of doping on crystallinity, crystallite size, strain induced in lattice, defects and electron-hole recombination rate were investigated. Optical band gap was calculated using Kubelka-Munk function from the diffuse reflectance spectra (DRS) obtained using ultraviolet visible (UV–Vis) spectroscopy. Finally, photocatalytic performance was studied from rhodamine B (Rh B) degradation and reaction kinetics were analyzed. Maximum degradation efficiency was obtained for 1.0 mol% N doped CuO NPs which also exhibited minimum band gap and lowest electron-hole recombination rate. For the optimum doping concentration, nitrogen was found to create oxygen vacancies while substituting oxygen in the lattice, and thus reduce electron-hole recombination rate and increase photocatalytic degradation rate effectively.

Photocatalytic activity of the biogenic mediated green synthesized CuO nanoparticles confined into MgAl LDH matrix

The global concern over water pollution caused by organic pollutants such as methylene blue (MB) and other dyes has reached a critical level. Herein, the Allium cepa L. peel extract was utilized to fabricate copper oxide (CuO) nanoparticles. The CuO was combined with MgAl-layered double hydroxides (MgAl-LDHs) via a co-precipitation method with varying weight ratios of the CuO/LDHs. The composite catalysts were characterized and tested for the degradation of MB dye. The CuO/MgAl-LDH (1:2) showed the highest photocatalytic performance and achieved 99.20% MB degradation. However, only 90.03, 85.30, 71.87, and 35.53% MB dye was degraded with CuO/MgAl-LDHs (1:1), CuO/MgAl-LDHs (2:1), CuO, and MgAl-LDHs catalysts, respectively. Furthermore, a pseudo-first-order rate constant of the CuO/MgAl-LDHs (1:2) was 0.03141 min−1 while the rate constants for CuO and MgAl-LDHs were 0.0156 and 0.0052 min−1, respectively. The results demonstrated that the composite catalysts exhibited an improved catalytic performance than the pristine CuO and MgAl-LDHs. The higher photocatalytic performances of composite catalysts may be due to the uniform distribution of CuO nanoparticles into the LDH matrix, the higher surface area, and the lower electron and hole recombination rates. Therefore, the CuO/MgAl-LDHs composite catalyst can be one of the candidates used in environmental remediation.

Is the trend toward a sustainable green synthesis of copper oxide nanoparticles completely safe for Oreochromis niloticus when compared to chemical ones?: using oxidative stress, bioaccumulation, and histological biomarkers.

Scientists worldwide have noticed that cutting-edge technologies can be used to produce nanoparticles (NPs) in a sustainable and environmentally friendly way, instead of the old methods. However, the effectiveness of this approach for aquatic environments and species still needs to be determined. Therefore, this study aims to compare between the toxicity of green and chemically synthesized copper oxide nanoparticles (GS and CS) CuO NPs at two different concentrations on Nile tilapia (Oreochromis niloticus) using various biomarkers. CuO NPs' formation was proved, and their different characterizations were recorded. Then, the fish samples were randomly allocated in glass aquaria into five groups: one acted as a control group, and the other groups were exposed to two concentrations (25 and 50mg/L) of GS-CuO NPs and CS-CuO NPs, separately, for 4days. After the experimental time, in all groups that were exposed to two concentrations of both synthesized CuO NPs, the results revealed that glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), and thiobarbituric acid reactive substances (TBARS) levels were elevated in the liver and gills compared to glutathione reduced (GSH) content, which showed a significant decline. Bioaccumulation of Cu was more prevalent in the liver than in the gills, and the highest bioaccumulation capacity was more evident in the groups exposed to CS-CuO NPs. Moreover, the bioaccumulation of Cu caused severe histological changes in the liver and gills. In conclusion, the results suggested that GS-CuO NPs revealed less toxicity than CS-CuO NPs to the examined fish. However, they are still toxic, and their toxic effect cannot be overlooked.

Preparation and Characterization of Copper Oxide CuO (II) nanoparticles Prepared by a Hydrothermal Method and for Solar Cells applications

Metal oxide nanoparticles were synthesized by a hydrothermal method inside a self-designed stainless steel autoclave, sealed, and heated at different temperatures. X-ray diffraction (XRD) analysis revealed the single-phase structure of CuO nanoparticles with an average grain size of 52.64 nm at temperatures of 100 °C, respectively. The EDX analysis determined that the sample was of high purity and did not contain impurities. Visible and ultraviolet spectroscopy identified a broad absorption band for CuO nanoparticles at a wavelength of 570 nm. Using the Tauc diagram, the bandgap was calculated, as its value was equal to 1.7 eV. The photovoltaic performance values of a solar cell are sensitized to the natural red dye extracted from beetroot. The solar cell produced a conversion efficiency of 2.08. The synthesized CuO nanoparticles could be potential candidates for use in electronic devices.

Camellia sinensis Assisted Synthesis of Copper Oxide Nanoparticles (CuONPs) and Assessment of Its Antioxidant Activity and Zebrafish Embryonic Toxicology Evaluation.

- Camellia sinensis,or oolong tea, is a partially fermented version of tea used in Asian countries. The remarkable reduction activity of the tea extract can potentially be used for synthesizing nanoparticles. Recently,Camellia sinensishas gained popularity for the formulation of some metal nanoparticles. Aim To formulate green synthesis of copper oxide nanoparticles (CuONPs) mediated byCamellia sinensis(oolong tea) and assess its cytotoxicity and antioxidant properties. Materials & Methods Oolong tea extract is prepared and added to CuSO4 solution to synthesize CuO nanoparticles (CuONPs). The centrifugation pellet of CuONPs is collected and subjected to DPPH (2,2 - diphenyl -1- picrylhydrazyl hydrate)and H2O2 assays. The cytotoxicity screening is performed using zebrafish embryos. Results The reducing activity of oolong tea successfully synthesizes the copper nanoparticles. High values are obtained in DPPH (63% inhibition at 10µL concentration, 73% inhibition at 20µL, 80% at 30µL, 85% at 40µL and 90% at 50µL concentrations) and H2O2 (50% inhibition at 10µL concentration, 65% at 20µL, 68% at 30µL, 75% at 40µL and 80% at 50µL concentrations) assays. There are no morphological deformities in the zebrafish and no loss of cell viability or delayed hatching at low concentrations (below 4-8 µL), as shown by the viable embryos with no morphological deformities. Conclusion The study has evidenced high antioxidant activity and minimal cytotoxicity of CuO nanoparticles produced usingCamellia sinensis, thus proving it to be a good biomaterial for a wide range of biological applications.

Green synthesis of copper oxide nanoparticles: Characterization and applications for environmental and biomedical fields

AbstractIn recent years, there has been an increasing interest in the development of plant‐based nanoparticles due to their numerous benefits over conventional physio‐chemical methods, including sustainability and environmental safety. Green synthesis, a process that produces safe and sustainable goods without the use of harsh chemicals or other harmful processes, is gaining popularity. The current study focuses on the green synthesis of copper oxide nanoparticles using Piper nigrum leaf extracts, their characterization, and applications. The synthesis of nanoparticles was confirmed by changes in colour, further endorsed by UV–visible spectroscopy. Copper oxide (CuO) nanoparticles were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). CuO nanoparticle sizes ranged between 58.23 and 69.89 nm and were spherical in shape. FTIR results indicated a functional group capped on the nanoparticle surface. The antibacterial activity of the copper oxide nanoparticles was tested, and they exhibited the significant decrease in bacterial concentration and the largest zone of inhibition, making them an efficient disinfectant. Antimicrobial activity against Bacillus subtilis and Escherichia coli was observed. Furthermore, the synthesized CuO nanoparticles exhibited a high affinity for safranin dyes and demonstrated maximum removal efficiency. This makes them an effective agent for removing dyes in wastewater from industries such as clothing manufacturing. Safranin dye was successfully removed with an efficiency of 78% using nanoparticles. In conclusion, the green synthesis of copper oxide nanoparticles using plant extracts presents an eco‐friendly and sustainable approach for producing nanoparticles with a wide range of potential applications.

Structural, Characterization, And Morphological Properties Of Copper Nanoparticles From Opuntia Ficus Indica Plant

AbstractOne of the most recent areas of interest in current nanotechnologies and nanosciences is the use of biomaterials in the manufacturing of nanoparticles. More and more research is being carried out on environmentally friendly methods to create metal oxide nanoparticles (NP), with the intention of preventing any potential risks associated with harmful substances for a safe and healthy environment. In this study, Copper Oxide (CuO) is synthesized utilizing Opuntia ficus‐indica as the plant extract using a Microwave Combustion Technique (MCM) and its comparison against the Conventional Combustion Method (CCM) are investigated. The synthesized CuO nanoparticles were characterized using X‐ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT‐IR), Scanning Electron Microscopy (SEM), and Energy Dispersive X‐ray Analysis (EDX) analysis. Photoluminescence spectroscopy was undertaken to acquire emission and absorption spectra and determine defects in the structures of all synthesized nanopowder samples. The antibacterial activity of the CuO nanoparticles was evaluated in‐vitro using gram‐negative and gram‐positive bacteria (Bacillus subtilis, Staphylococcus aureus). Enhanced anti‐bactericidal activity was shown against Gram‐negative bacteria compared to Gram‐positive bacteria. Through these findings, the use of CuO using Opuntia ficus indica extracts is hereby shown to be a cost‐effective and environmentally friendly alternative and that can be used in a variety of applications.

Electrochemical Sensor Based on CuO Nanoparticles-Modified Graphite Electrode for the Detection of Malachite Green

In this study, the development of a graphite paste electrode (GPE) modified by copper oxide nanoparticles (CuO@GP) to be used as a practical and economical sensor for the electrochemical sensing of malachite green (MG) has been elucidated. The sol–gel technique was applied for the synthesis of CuO nanoparticles (NPS) from copper chloride (CuCl[Formula: see text], where the surfactant cetylpyridinium chloride (C[Formula: see text]H[Formula: see text]NCl) played the role of a capping agent. The synthesized CuO NPS were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). A bare GPE was modified using these CuO NPS and thus developed; the new electrode was used as a working electrode (WE) in a 3-electrode system for studying the cyclic voltammetry (CV) and differential pulse voltammetry (DPV) responses of MG. Phosphate buffered saline (PBS) with a pH value of 6 was used as the optimum buffer. Using DPV, a widely linear operational range of 1–1000 [Formula: see text]M was obtained with a detection limit of 0.18 [Formula: see text]M. This CuO@GP provided excellent repeatability, reproducibility and prolonged stability for the MG molecule. For the selectivity study, various common interfering agents were used to observe MG’s corresponding peak current variation. Moreover, this electrode demonstrated a successful application for detecting MG in pond water and fish flesh. This method is effective for similar other applications.

Optical Conductivity Analysis of Green CuO Nanoparticles Using Plant Leaf Extract

The optical properties of green synthesized CuO nanoparticles such as absorption coefficient, refractive index, band gap, dielectric constant and optical conductivity were analyzed. XRD shows that upon temperature treatment of green CuO nanoparticles, the crystal size increases and thus the crystallinity increases due to the decrease in the number of crystals per unit area. Due to the high crystallinity, the absorption coefficient exhibits a high electronic shift and the refractive index exhibits good polarization of the ions. Thus the dielectric constant of the real and imaginary regions decreases as the photon energy increases. Higher temperatures exhibit higher photon energy levels. Optical conductivity has induced electron annihilation due to the absorption coefficient of increased photo energy light; Hence the optical conductivity analysis of Lantana camara capped CuO nanoparticles indicated the stability of electrical conductivity with increase in photo power.

Green synthesized CuO nanoparticles using macrofungi extracts: Characterization, nanofertilizer and antibacterial effects

In this detailed study, copper oxide nanoparticles (CuO NPs) are synthesized using the green synthesis method via the extracts of Rhizopogon roseolus (R) and Coprinus comatus (Co) macrofungi. Additionally, the effect of calcination temperature on the formation of CuO NPs is investigated at different temperatures such as 400, 600, 800 °C during the synthesis process. The structural, optical and morphological characterizations of biosynthesized CuO NPs are performed by XRD, FT-IR, UV–Vis spectroscopy and SEM-EDX analysis, respectively. From the XRD results, it is determined that CuO NPs formed in monoclinic structure in all samples. Also, the optical band gap values in UV–vis spectroscopy are approximately 1.3–1.4 eV for all calcination temperatures. As for SEM measurements, it is clearly seen that the particles have irregular planar morphology in a certain order. Also, the possibilities of using CuO NPs produced at different calcination temperatures as nanofertilizer at different concentrations are determined via analyzing the effects on the growth of Lepidium sativum (cress), Raphanus sativus (radish) and Zea mays (corn) seeds. Besides, it is found that the concentration values of 62.5 (for R) and 125 ppm (for Co) are more effective in the growth and development of all three seeds for all calcination temperatures. Further, the antibacterial effect of CuO NPs is tested against six bacterial strains (Y. enterocolitica, B. cereus, E. faecalis, S. aureus, P. aeruginosa, and A. baumanni) by using the Kirby Bauer disk diffusion technique. The results indicate that CuO NPs calcined at 400 °C have the highest antibacterial effect. All in all, the novelty of this study is related with the production of CuO NPs with the aid of the extracts of macrofungi such as R. roseolus and C. comatus.

Synthesis of Cu2O Nanoparticles by Ellipse Curve Micromixer.

Micromixers offer the advantage of rapid and homogeneous mixing compared with conventional macroscale reaction systems, and thus they show great potential for the synthesis of nanoparticles. An ellipse curve serpentine micromixer, which had been proposed in our prior works was employed to synthesize Cu2O nanoparticles. Cu2O are excellent photocatalysts that have been widely utilized in the degradation of organic dyes. Owing to the excellent mixing performance, the reduction of Cu(OH)2 in micromixing synthesis was more sufficient than that in conventional stirring synthesis. The Cu2O nanoparticles synthesized by micromixing had smaller size and narrower size distribution compared with those synthesized by stirring in a beaker. The smallest Cu2O nanoparticles were obtained by micromixing with Re = 100 at T = 60 °C, while the most uniform Cu2O nanoparticles were obtained at T = 80 °C owing to Ostwald ripening. Through the photocatalytic degradation experiments of Rhodamine B, the Cu2O nanoparticles synthesized by micromixing were found to have better photocatalysis than those synthesized by stirring. The research results showed that the micromixing synthesis was a more suitable choice to produce Cu2O nanoparticles with excellent photocatalysis. The ellipse curve micromixer with a simple structure and high mixing performance can be applied in the synthesis of various nanoparticles.