Ratio Of CuO Research Articles

Fabrication of visible light active Sn-doped ZnS@CuO composites for wastewater remediation

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

Synthesis of CuO/Fe3O4 Nanocomposite for enhanced solar thermal desalination

Nanoparticle (NPs) have attracted the attention of scientists and researchers in water remediation due to the improvement in its processability, and its cost effectiveness. The present work analyzed the synergistic effect of CuO (NPs) with different ratios (0, 0.5, 0.6, 0.7, 0.8, 0.9 and 1 wt %) on the structural, and optical properties of Fe3O4 (NPs), that can be used in water desalination process. The general methodology for preparation and structural properties of CuO (NPs), Fe3O4 (NPs) and CuO/Fe3O4 (NCs) were analyzed by (XRD) and (TEM) measurements. The morphological combination of (SEM) with (EDX), were used for determining the elemental identification of CuO/Fe3O4 (NCs). The characterization topography was found to be strongly affected by the change of the CuO concentration. Furthermore, the Urbach energy (EU), steepness parameter (σ), electron-phonon interaction (Ee-p), optical band gap (Eg), refractive index (n) and optical conductivity (σopt) were calculated. The optical absorption studies in the UV–Visible region, revealed that the CuO/Fe3O4 (NCs) was found to be direct allowed transition, and the energy bandgap value decreased from 2.52 eV to 2.15 eV based on the percentage change of CuO (NPs) in CuO/Fe3O4 (NCs). Moreover, the value of thermal conductivity (k), and thermal efficiency (η), showed an increase with the increase of the ratio of CuO (NPs), which may be an indication for opening an innovation way that can satisfy the need of seawater desalination technology.

Fabrication, structure and optical characteristics of CuO/polymer nanocomposites materials for optical devices

The films of P(4ClAni)/CuO, which formed of mixing poly 4-chloroaniline P(4ClAni) by CuO, were fabricated by the casting solution method. The XRD confirmed the successful prepration of the P(4ClAni)/CuO films. Additionally, the effect of CuO on the optical characteristics was determined. The CuO increased the refractive index from 1.09 for P(4ClAni) to 1.11 for P(4ClAni)/CuO-1, and 1.19 for P(4ClAni)/CuO-3, respectively, while the oscillation energy E0 dropped from 4.29 eV for P(4ClAni) to 3.57 eV for P(4ClAni)/CuO-1, 3.12 eV for P(4ClAni)/CuO-2, and 3.06 eV for P(4ClAni)/CuO-3. The charge transfer between P(4ClAni) and CuO increased optical conductivity as the CuO ratios increased. This suggests that modifications in the electronic structure of the composite due to the interactions between P(4ClAni) and CuO. Also, the plasma frequency increased from 0.87 x 1012 s−1 to 2.32 x 1012 s−1. These changes in optical parameters occurred when the polarization of the P(4ClAni)/CuO was altered. The study elucidated the advantages of incorporating CuO nanoparticles as fillers in improving the properties of P(4ClAni) structures. The obtained results indicate the P(4ClAni)/CuO composites were sucessfuly fabricated with novel characteristics that can be applied in flexible optical devices.

Selective catalytic oxidation of DMF over Cu-Ce/H-MOR by modulating the surface active sites

Selective catalytic oxidation of the hazardous DMF exhaust gas presents a significant challenge in balancing oxidation activity and products selectivity (CO, NOx, N2, etc.). It is found that Cu/H-MOR demonstrates superior performance for DMF oxidation compared to CuO on other supports (γ-Al2O3, HY, ZSM-5) in terms of product selectivity and stability. The geometric and electronic structures of CuO active sites in Cu/H-MOR have been regulated by CeO2 promoter, leading to an increase in the ratio of active CuO (highly dispersed CuO and Cu+ specie). As a result, the oxidation activity and stability of the Cu/H-MOR catalyst were enhanced for DMF selective catalytic oxidation. However, excessive CuO or CeO2 content led to decreased N2 selectivity due to over-high oxidation activity. It is also revealed that Ce3+ species, active CuO species, and surface acid sites play a critical role in internal selective catalytic reduction reaction during DMF oxidation. The 10Cu-Ce/H-MOR (1/4) catalyst exhibited both high oxidation activity and internal selective catalytic reduction activity due to its abundance of active CuO specie as well as Ce3+ species and surface acid sites. Consequently, the 10Cu-Ce/H-MOR (1/4) catalyst demonstrated the widest temperature window for DMF oxidation with high N2 selectivity. These findings emphasize the importance of surface active sites modification for DMF selective catalytic oxidation.

Some characteristics of Cu/Cu2O/CuO nanostructure heterojunctions and their applications in hydrogen generation from seawater: effect of surface roughening

Cu/Cu2O/CuO heterojunction were synthesized, using thermal oxidation under the flow of argon and oxygen gas mixture, as efficient photoelectrode for hydrogen generation. The Cu/Cu2O/CuO heterojunction were synthesized using un-roughed and roughed Cu foils. The resulting heterojunction samples were characterized using various techniques. The evaluated oxide layer (Cu2O/CuO) thicknesses for un-roughed and roughed samples are 4.2 and 8.5 μm, respectively. XRD revealed that the oxide layer is a mix cubic Cu2O and monoclinic CuO crystalline phases with higher CuO ratio in the roughed sample. The surface morphology of the un-roughed sample is a porous surface that consisting of nanoflakes whereas surface morphology of the roughed sample is randomly oriented nanowires. The Cu/Cu2O/CuO nanostructured surface is superhydrophilic, with water contact angles of 11.12 and 0° for un-roughed and roughed samples, respectively. The roughed sample has higher absorbance over the entire studied wavelength range. The obtained values of the optical band gap for un-roughed and roughed samples are 2.48 and 2.39 eV, respectively. The photocurrent density of the roughed photoelectrode is much greater than that of un-roughed photoelectrode. The roughed photoelectrode has a photocurrent density of—0.151 mA cm−2 at—0.85 V and a photoconversion efficiency of 0.55% when illuminating with 340 nm light. This work offers a promised Cu/Cu2O/CuO photoelectrode for hydrogen generation from seawater.

Visible light-assisted S-scheme p- and n-type semiconductors anchored onto graphene for increased photocatalytic H2 production via water splitting

This work reports on photocatalytic hydrogen (H2) production via water splitting by synthesizing CuO and ZnO semiconductors anchored onto graphene by varying the mass ratios of CuO and ZnO into the graphene matrix. The high H2 production performance for binary nanocomposite (CuO/ZnO) compared to its components confirms the synergistic effect between ZnO and CuO nanoparticles. Introducing 10 wt% graphene into CuO and ZnO displayed the highest H2 production reaching to 37.2 mmol/g.h, which was 3.29 times higher than pristine binary nanocomposite (CuO/ZnO). The graphene played a critical role in enhancing the photocatalytic activity of CuO and ZnO towards H2 production, owing to the accelerated transport of photo-excited electrons between the semiconductors. Under the optimum conditions, H2 production by 10 % of graphene into CuO and ZnO reached a maximum value of 48.6 mmol/g.h when Na2S/Na2SO3 was used as a sacrificial agent. The charge transfer carriers were monitored to explain the photocatalytic H2 production mechanism based on the optical property characterizations and S-scheme heterojunction system. An excellent reusability was achieved after five consecutive cycles of H2 production reaction. The outcome of this research introduces a reusable and effective catalyst with a facile and easy configuration for energy production applications and confirms that the decoration of semiconductors on graphene could be a promising strategy for highly-efficient photocatalytic H2production. Furthermore, by offering a clean alternative to fossil fuels and reducing greenhouse gas emissions—especially when produced from renewable sources—hydrogen can significantly contribute to achieving sustainable development goal 7 (SDG 7), thus advancing toward a more sustainable, equitable future.

Controlled sputter deposition of oxide nanoparticles-based composite thin films

This study explores the feasibility of deposition of composite films based on nanoparticles (NPs) using a magnetron-based gas aggregation source of NPs. First, we investigate the deposition conditions and properties of the individual components of the composite films, namely, NPs prepared using Cu and W targets. We thoroughly discuss that the generation of NPs might be more efficient in the Ar atmosphere in the case of W target due to an enhanced direct emission of NP seeds from the target and/or a longer lifetime of the seeds in the plasma. To operate reasonable fluxes of NPs for both targets, O2 was added into the gas mixture. Lower O2 flow rates promote enhanced seed formation of NPs, while higher flow rates exhibit a dominant target poisoning effect, reducing the flux of NPs. We demonstrate that a fine-tuning of O2 flow rate allows us to control the resulting crystal structure of the NPs. Fully oxidized NPs were produced at O2 flow rates of 1.30sccm and 1.50sccm for Cu and W targets, respectively. Subsequently, CuO/WO3 composite films were prepared using our in-house-built software as alternating NPs-based layers. To demonstrate the capabilities of the deposition technique, three different CuO/WO3 multilayers were prepared, each with a specific thickness of the individual layers (80nm, 40nm, and 10nm, which corresponds to a monolayer of NPs). Scanning electron microscopy imaging shows well-defined layers with the intended thickness. In addition, XRD analysis confirms that all three multilayers exhibit practically identical patterns, indicating the same volumetric ratio of CuO and WO3 NPs in the investigated films.

CuO:V2O5 driven alterations in dielectric, ferroelectric and structural properties of Barium Zirconate Titanate ceramics

This study focuses on the properties of Vanadium and Copper co-doped Barium Zirconate Titanate (BZT) for potential technological applications. Various doping ratios of CuO:V2O5 were used to synthesize the materials, and X-ray diffraction (XRD) confirmed a tetragonal phase in all samples. The grain density and dimensions decreased with higher concentrations of V2O5 and CuO. FTIR spectra confirmed the compositional structure and bonding of the samples. The impedance analysis indicated that higher doping concentrations facilitated charge conduction at grain boundaries. Dielectric relaxation was studied using the Havriliak–Negami model and electrical modulus behavior was analyzed. Activation energy values from Arrhenius fitting matched those from impedance data, suggesting the same type of charge carriers. The study revealed that elevated levels of V concentration induced charge carriers to exhibit hopping behavior, thereby enhancing conductivity. Conversely, higher Cu concentration impeded hopping, leading to a swift rise in activation energy.

Carbon dioxide and nitrate co-electroreduction to urea on CuOxZnOy

Urea is a commonly used nitrogen fertiliser synthesised from ammonia and carbon dioxide using thermal catalysis. This process results in high carbon dioxide emissions associated with the required amounts of ammonia. Electrocatalysis provides an alternative method to urea production with reduced carbon emissions while utilising waste products like nitrate. This manuscript reports on urea synthesis from the electroreduction of nitrate and carbon dioxide using CuOxZnOy electrodes under mild conditions. Catalysts with different ratios of CuO and ZnO, synthesised via flame spray pyrolysis, were explored for the reaction. The results revealed that all the CuOxZnOy electrocatalyst compositions produce urea, but the efficiency strongly depends on the metal ratio composition of the catalysts. The CuO50ZnO50 composition had the best performance in terms of selectivity (41% at −0.8 V vs RHE) and activity (0.27 mA/cm2 at −0.8 V vs RHE) towards urea production. Thus, this material is one of the most efficient electrocatalysts for urea production reported so far. This study systematically evaluates bimetallic catalysts with varying compositions for urea synthesis from carbon dioxide and nitrate.

Assessment of Conductivity through Impedance Analysis of CuO:Ho2O3 Modified BaZr0.05Ti0.95O3

The solid state reaction method was used to prepare 2 wt% of BaZr0.05Ti0.95O3 doped by (CuO:Ho2O3) in different ratios. The variation in the ratio of CuO:Ho2O3 was fixed at 1:1, 1:2, 1:3, 2:1 and 3:1. The dielectric data and impedance analysis confirmed the non-Debye nature of all the samples. Conductivity results show the Non-overlapping Small Polaron tunnelling conduction mechanism up to 240 °C and the Co-related Barrier Hopping conduction mechanism after 240 °C in the selected temperature range for all the samples. For the Co-related Barrier Hoping model, a sample with a ratio of 1:3 has shown the maximum binding energy value for the charge carrier and a comparatively lesser value of conductivity.

Bimetallic CuO−ZnO Hybrid Nanocomposite Materials for Efficient Remediation of Environmental Pollutants

AbstractPure CuO and 2‐Dimentional CuO−ZnO nanocomposites (NCs) were effectively prepared by an ultrasound‐assisted probe sonication route for different ratios of CuO and ZnO, and the multifunctional properties were investigated by the application of the advanced methods. XRD (X‐ray diffraction) patterns revealed a crystallite size (D) range of 25 to 31 nm for pure CuO and CuO−ZnO NCs. According to calculations, the energy band gap value (Eg) for the NCs is between 2.15 and 2.48 eV. Under UV light irradiation, the photocatalytic degradation of pure CuO and CuO−ZnO NCs on Direct Green (DG) and Fast Blue (FB) dyes was assessed. 60 mg of the catalyst was added to 20 ppm solutions of DG and FB dye. The stock solution of the dyes was prepared 10, 15, 20 and 25 ppm of 250 ml dye solution. Electrochemical analysis using cyclic voltammetry revealed improved redox potential output in the electrode crafted with graphite powder in 0.1 N HCl electrolyte solution. These NCs were used because of their capacity to detect an extremely dangerous chemical like arsenic. The constructed electrode‘s lowest limit of detection was determined to be 110–3 mol/L. In general, vertical linearity was seen in all of the prepared nano‐electrodes, especially above 150 ohms with real axis for pure CuO but beyond 100 ohms for doped electrodes. Based on our study, we conclude that the CuO and ZnO NCs, containing 10 % of ZnO, were the most effective photocatalyst for DG and FB dyes and electrochemical sensor for Arsenic.

Studies on resistive-type humidity sensing properties of copper-zinc mixed metal oxide nanostructures

The present work reports the synthesis of CuO-ZnO nanostructured thin films by in-situ low-cost nebulized assisted spray pyrolysis system. The physicochemical properties of the prepared samples were measured using various characterization techniques. X-Ray Diffraction (XRD) studies confirmed the formation of crystalline CuO-ZnO nanostructures and revealed hexagonal wurtzite-type crystal structure. The appearance of CuO-ZnO nanostructures was also confirmed using Fourier Transform Infrared Spectroscopy (FTIR). Optical characterization showed that optical reflection of CuO-ZnO initially increased with increase in CuO in the sample and then decreased. The same trend was observed for band gap energy values which varied from 3.87 eV to 4.01eV with change in molar ratio of CuO and ZnO in the sample. SEM analysis revealed the change in morphology of CuO-ZnO nanostructures with change in molar ratio of CuO and ZnO in the composite. Further, the humidity sensing behavior of the prepared nanostructured thin films was investigated in the range of 30 % to 90% relative humidity. The results obtained showed that the resistance of the prepared films decreased with increasing relative humidity (RH). The nanostructures with CuO (60%) − ZnO (40%) exhibited superior humidity sensing performance which was stable with sensitivity of about 2.33 MΩ/%RH (at 57 % RH); and response-recovery time of 29 s and 16 s respectively.

Preparation of CuO/rGO Nanocomposite with Rice Granular Structure and Its Application to Detect Glucose

In order to enhance the electrochemical detection performance for glucose, graphene oxide (GO) was introduced during the preparation process of micron-sized rice granular CuO. A nano-sized rice CuO/rGO composite chemically modified electrode with good conductivity was prepared and used for the enzyme-free detection on glucose. The morphology and structure of the samples were characterized by scanning electron microscope, X-ray diffraction, Raman spectroscopy and N2 adsorption desorption tester. The electrochemical properties of the prepared modified electrode were tested by cyclic voltammetry, amperometric experiments and AC impedance testing. The results show that the prepared nanocomposite still retains the rice grain structure of the original CuO, but the particle size is reduced in to nanometer scale. When the mass ratio of CuO and rGO is 3.5:1, the modified electrode has the strongest current response to glucose: in the range of 0.01 to 2.53 mmol·l−1, there is a good linear relationship and the linear equation is I pa (Ma) = (2.81 ± 0.08) × 10−2 + (9.63 ± 0.06) × 10−2 c (mmol·l−1), R = 0.999. The detection limit is 0.047 mol·l−1 (S/N = 3) and the sensitivity is 1746.16 μA·mmol−1·L·cm−2. At the same time, the prepared modified electrode has good selectivity, reliability, repeatability and stability for glucose.

Broccoli-shaped nano florets-based gastrointestinal diseases detection by copper oxide chitosan

This report describes a simple and inexpensive room-temperature chemo-resistive CuO-Chitosan-based hydrogen sensor for detecting gastrointestinal diseases (GIDs). A clinical analysis shows that GID patients exhale more than 10–20 ppm of hydrogen compared to healthy people, which is considered a biomarker for the non-invasive diagnosis of GIDs. This allows for a portable, non-intrusive, effective, and fast-detecting sensor in treating GIDs. To our knowledge, no GIDs study has used chitosan for H2 sensing. The current study prepares CuO-Chi nanocomposites and tests their hydrogen sensitivity for GIDs detection. Different ratios of CuO: chitosan [CuO: Chi (A(1:2), B(1:1), C(1:0.5), D(1:0.25), E(1:0.125), and F(1:0.0625)]were synthesized using novel co-precipitation cum probe sonication technique. Compared to other CuO composites in the literature, our synthesized CuO: Chi-B (1:1) can detect as low as 10 ppm of hydrogen gas at room temperature, with a lower limit of detection (0.07 ppm) and a regression coefficient (R2) of 0.9566. The Contact angle explains the anti-wettability property with the increase in the hydrophilicity due to the presence of electronegative atoms like N in NH2 and O in the OH group. Field emission scanning electron microscopy reveals several single broccoli nano florets. Most importantly, the sensor's calculated Brunauer–Emmett–Teller surface area is 5.1565 m2/g with a pore volume of 0.02173cm2/gm and pore size of 16.897 nm. It has excellent sensitivity, response, recovery, reproducibility, stability, and selectivity. The reaction mechanism for sensor performance is elaborately discussed by the Grotthuss mechanism. The above studies suggest and show that CuO: Chi-B (1:1) is a new material for hydrogen sensors that can be used for the breath analysis to detect GIDs at 10 ppm.

Non-enzymatic amperometric glucose sensing on CuO/mesoporous TiO2 modified glassy carbon electrode.

The present study illustrates the fabrication of a glucose sensing electrode based upon binary composite of copper oxide and mesoporous titanium dioxide on glassy carbon (CuO/TiO2/GCE). The X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis evidently showed the phase pure monoclinic CuO nanoparticles and anatase TiO2. N2 adsorption-desorption analysis verified the mesoporosity in TiO2 with specific surface area greater than 105 m2 g-1. Electrochemical impedance spectroscopic analysis proved the remarkable decrease in the charge transfer resistance and facilitation of electron transfer process on the fabricated electrode. The optimum weight ratio of CuO to TiO2 was 1 : 1, and the optimum potential was 0.6 V vs. saturated calomel electrode. The chronoamperometric measurements displayed a detection limit of 1.9 μM, and sensitivities of 186.67 μA mM-1 cm-2 and 90.53 μA mM-1 cm-2 in two linear ranges of 0.05 to 5.2 mM and 5.2 to 20 mM, respectively. The amperometric analysis further showed good reproducibility, high specificity and outstanding stability of the modified electrode.

Coaxial electrospinning synthesis of size-tunable CuO/NiO hollow heterostructured nanofibers: Towards detection of glucose level in human serum

Nanofibers (NFs) have found wide applications by virtue of their particular morphology and high specific surface area. In this study, size-tunable hollow CuO/NiO NFs were synthesized by coaxial electrospinning and subsequent calcination. The synthesized hollow CuO/NiO NFs owned large specific surface area for catalytic active sites. In addition, the formation of heterostructure interface between CuO and NiO was beneficial to improve the electrocatalytic performance. As non-enzymatic electrode material, the synthesized CuO/NiO NFs exhibited superior electrocatalytic capability for glucose oxidation. When the molar ratio of CuO to NiO is 0.4, the composite NFs achieved the optimal electrocatalytic ability for glucose oxidation, performing high sensitivity of 1324.17 μA mM−1 cm−2 and wide liner range from 1 to 10,000 μM. The constructed electrode has been utilized to detect glucose concentration in real serum with excellent recovery, indicating that CuO/NiO hollow heterostructured NFs are promising materials for biomedical applications.

Molecular dynamics and steady-state process simulation coupled research on CCLG system design for cleaner production of EG

BackgroundThe CO2 capture technologies such as chemical-looping gasification (CLG) and reformation (CLR) receive more and more attention under the globally warming environment. In this paper, the mechanism of coal chemical-looping gasification (CCLG) process with copper-based oxygen carrier is analyzed by molecular dynamics (MD) simulation and steady-state process simulation to produce high purity ethylene glycol (EG). MethodsFirstly, the effect of temperature and mass ratio of coal and CuO on CCLG process are investigated with gasification experiments. Secondly, the MD simulations in ReaxFF force field are performed in purpose of obtaining the micro-level information and cross-reference with experimental results. Finally, an innovative process to produce high purity EG is designed based on CCLG process from the above simulations and experiment results. Significant findingsThe results of gasification experiments show that the optimal reaction temperature is 850°C and the optimal mass ratio of coal to CuO is 1:1.5. The results obtained from the MD simulations are found accordant with the experimental results. The EG targeted CCLG process basically meets the mass ratio required by the production of EG, and the CO2 emissions of the whole process is only 0.018 kg-CO2/kg-EG.

Strong near infrared photoluminescence from Sn doped Cu2O

Photoluminescence (PL) is a direct embodiment of photoelectric characteristics of a material. In this work, tin (Sn) doped cuprous oxide (Cu2O) Cu2O:Sn was prepared through mixing copper oxide (CuO) and tin sulfide (SnS) and annealing in nitrogen. By optimizing the mole ratios of CuO to SnS and annealing temperature, a new and strong near infrared PL (842 nm) was observed at room temperature in the prepared polycrystalline Cu2O:Sn. The 842 nm luminescence can be ascribed to the transition of carriers from Sn impurity level to the valence band edge of Cu2O. The results indicate that Cu2O:Sn has good photoelectric properties and Sn doping of Cu2O is a promising approach to improve the performance of Cu2O photoelectric devices.

Bifunctional Purposes of Composite TiO2/CuO/Carbon Dots (CDs): Faster Photodegradation Pesticide Wastewater and High Performance Electromagnetic Wave Absorber

The multifunction material for EMI absorber and photocatalytic of composite TiO2/CuO/Carbon Dots (CDs) by S-scheme has been successfully fabricated composite by the solid-state method as a green photocatalyst. In this work, the CDs were synthesized from Senna Siamea seeds by solid-state method for various calcination temperatures: 250°C, 275°C, and 300°C. The CDs is used to help electron/hole charge in the photocatalysts system and for enhancing electromagnetic wave absorber. The wt.% of TiO2 for every composition keep constant is 50% and the ratio of CuO: CDs was various: 45:5, 40:10, and 30:20 for every calcination temperature of CDs. The surface morphology was sticky-tiny-balls-like shape indicating the CDs were attached and sticky surrounds TiO2 and CuO. For the size, the grain distribution increase with increasing calcination temperature which consistent with diffraction spectra, confirm that the CDs were successfully doped in composites TiO2/CuO/CDs. The composite TiO2/CuO/CDs show high electromagnetic wave absorber with efficiency 90% indicated by the reflection loss below -10 dB with working frequency from 5.54 to 6.76 GHz and the bandwidth from 1.4 to 1.8 GHz. The best photocatalytic performance is for TiO2: CuO: CDs is 50: 45: 5 with temperature calcination CDs 250°C which was degraded fipronil pesticide for the concentration of 0.05% up to 62% only for 15 minutes and shows high stability up to fourth cycles. The four-time cycles of pesticide show high stability with degradation >58% indicated that the TiO2/CuO/CDs material, effective and efficient energy for mass production pesticide wastewater. The composite in this study shows high potentials as a new bi functional material with high photocatalytic pesticide performance and absorber electromagnetic waves.

A new CuO/TiO2 nanocomposite: An emerging and high energy efficient electrode material for aqueous asymmetric supercapacitors

The key to energy conversion and storage for supercapacitors is the development of easy-to-prepare electrode materials with high capacity performance. We have synthesized a series of nanocomposites based on copper oxide (CuO) and titanium dioxide (TiO2), symbolized as CuO/TiO2 with varying wt% Firstly, the current research uses a low-cost wet chemical method for high-performance asymmetric supercapacitor (ASC) ratios of CuO. Nanocomposites formation and morphological evaluations were confirmed via a series of characterization techniques, e.g., SEM, XRD, Raman, and XPS certified the highly crystalline nature and purity of the samples. The electrochemical properties were tested using the conventional three and two-electrode system that exhibited an excellent energy storage performance even at a low current of 1 A g−1. The TiO2-30 % CuO electrode had a greater specific capacitance of 553 F g−1 than pure CuO (226 F g−1) and TiO2 (115 F g−1) at the constant discharge current density of 1 A g−1.Moreover, an ASC was assembled by utilizing a TiO2-30 % CuO electrode and activated carbon (AC) as positive and negative electrodes respectively. The TiO2-30 % CuO//AC ASC delivered a high energy density of 34 Wh kg−1 at 800 W kg−1 and retained 18 Wh kg−1 when the specific power increased to 4800 W kg−1 at 1 A g−1. Our ASC exhibited excellent stability of 96 % retention after 10,000 cycles with superb rate capability at a wide voltage frame of 1.6 V. According to density functional theory calculations, CuO/TiO2 improved the material's electrical conductivity and electrochemical performance. The data suggested that the CuO/TiO2 nanocomposites, with optimum concentration of CuO, could be used as a good supercapacitor electrode material in the future.