Cuprous Oxide Research Articles

Interfacial strengthening and antibacterial behavior in an ultrafine-grained Zn-Ag-based biocomposites fabricated by the Cu2O-induced in situ wetting approach

Nowadays, Zinc (Zn)-based biocomposites as biodegradable implant materials have been recognized as a promising approach to overcome the insufficient mechanical performance of Zn matrix and to endow the Zn-based materials with biofunctionality. However, the strengthening effect on Zn-based matrix composite remains far from expectation mainly due to the poor interfacial bonding between the reinforcement and Zn matrix, and the relatively coarse grain size of the Zn matrix. Herein, we have developed a novel in situ wetting strategy to ameliorate the interfacial bonding and mechanical performance of Zn-Ag-based composites using cuprous oxide-modified graphene oxide (Cu2O-GO) sheets as reinforcement. The enhanced interfacial bonding between GO sheets and Zn matrix owing to the in situ generated ZnO interlayer and the ultrafine microstructure with an average grain size of 360 nm were simultaneously achieved in the hot extruded (HEed) 1 wt%Cu2O-GO/Zn-2 wt%Ag biocomposites. Consequently, HEed biocomposites possessed excellent tensile properties, including ultimate tensile strength (UTS) of 344.0 ± 2.4 MPa, yield stress (YS) of 314.0 ± 4.8 MPa, and elongation at failure of 15.5% ± 1.3%. Ultrafine and uniform microstructure of the HEed biocomposites resulted in a relatively uniform corrosion morphology and a degradation rate of 0.195 ± 0.004 mm y−1 in simulated body fluid (SBF) solution. The 2-fold diluted extract of the HEed biocomposites exhibited satisfying cytocompatibility with MC3T3-E1 pre-osteoblast comparable to that of Ti-6Al-4 V ELI alloys. More importantly, the synergistic effect of metallic ions, Ag-rich nanoparticles, and GO sheets contributed to the remarkable antibacterial activity of the experimental biocomposites against both S. aureus and E. coli. These results demonstrated that the 1Cu2O-GO/Zn-2Ag biocomposites should be anticipated as a promising biodegradable material for orthopedic applications.

Platinum (Pt), gold (Au), and silver (Ag) ohmic contacts to cupric oxide (CuO) films deposited by air-based sputtering and thermal annealing

The present work reports the fabrication of three different ohmic contacts (platinum (Pt)/CuO, gold (Au)/CuO, and silver (Ag)/CuO). Structural properties of the films measured by X-ray diffraction and Raman techniques confirmed that the Cu2O films prepared by DC sputtering using air as a reactive gas, transformed into pure CuO films after thermal annealing. The band gap of the CuO films of 1.33 eV was estimated by reflectance measurements. Hall measurements confirmed the p-type conductivity of the CuO films with an acceptor concentration of 2.04x1016 cm−3.The linear behavior in both directions of polarization observed in the current–voltage measurements confirmed the formation of ohmic contacts between the characterized three metals and CuO. Based on the slope of the current–voltage curve, the best ohmic contact was that fabricated between Au and CuO. The mechanism governing the transport through the interface between the metal/CuO ohmic contact was thermionic emission.

Enhanced performance of β-cyclodextrin modified Cu2O nanocomposite for efficient removal of tetracycline and dyes: Synergistic role of adsorption and photocatalysis

In recently year, cuprous oxide(Cu2O) has been proved to be an important photocatalyst for fast removal of contaminants. However, as we known that the single Cu2O cannot get the satisfactory degradation efficiency. Herein, a new photocatalyst was prepared by coating β-cyclodextrin on Cu2O(CuCD) under mild hydrothermal conditions, reducing the particle size of cuprous oxide from 200 nm to 40 nm. The as-prepared CuCD exhibit excellent photocatalytic activity, which degradation rate of tetracycline(TC), methylene orange(MO) and congo red(CR) increased by 2.0, 1.7 and 2.1 times, respectively, compared to pristine Cu2O in reaction system. This design confirms the synergistic effect of adsorption and photocatalysis due to the introduction of β-cyclodextrin on Cu2O, which can provide mass and electron transfer channels to accelerate the separation and migration of photogenerated electrons. Overall, this work provides an important step in developing Cu2O-based hybrids for wastewater treatment.

An extensive study on multiple ETL and HTL layers to design and simulation of high-performance lead-free CsSnCl3-based perovskite solar cells

Cesium tin chloride (CsSnCl3) is a potential and competitive absorber material for lead-free perovskite solar cells (PSCs). The full potential of CsSnCl3 not yet been realized owing to the possible challenges of defect-free device fabrication, non-optimized alignment of the electron transport layer (ETL), hole transport layer (HTL), and the favorable device configuration. In this work, we proposed several CsSnCl3-based solar cell (SC) configurations using one dimensional solar cell capacitance simulator (SCAPS-1D) with different competent ETLs like indium–gallium–zinc–oxide (IGZO), tin-dioxide (SnO2), tungsten disulfide (WS2), ceric dioxide (CeO2), titanium dioxide (TiO2), zinc oxide (ZnO), C60, PCBM, and HTLs of cuprous oxide (Cu2O), cupric oxide (CuO), nickel oxide (NiO), vanadium oxide (V2O5), copper iodide (CuI), CuSCN, CuSbS2, Spiro MeOTAD, CBTS, CFTS, P3HT, PEDOT:PSS. Simulation results revealed that ZnO, TiO2, IGZO, WS2, PCBM, and C60 ETLs-based halide perovskites with ITO/ETLs/CsSnCl3/CBTS/Au heterostructure exhibited outstanding photoconversion efficiency retaining nearest photovoltaic parameters values among 96 different configurations. Further, for the six best-performing configurations, the effect of the CsSnCl3 absorber and ETL thickness, series and shunt resistance, working temperature, impact of capacitance, Mott–Schottky, generation and recombination rate, current–voltage properties, and quantum efficiency on performance were assessed. We found that ETLs like TiO2, ZnO, and IGZO, with CBTS HTL can act as outstanding materials for the fabrication of CsSnCl3-based high efficiency (η ≥ 22%) heterojunction SCs with ITO/ETL/CsSnCl3/CBTS/Au structure. The simulation results obtained by the SCAPS-1D for the best six CsSnCl3-perovskites SC configurations were compared by the wxAMPS (widget provided analysis of microelectronic and photonic structures) tool for further validation. Furthermore, the structural, optical and electronic properties along with electron charge density, and Fermi surface of the CsSnCl3 perovskite absorber layer were computed and analyzed using first-principle calculations based on density functional theory. Thus, this in-depth simulation paves a constructive research avenue to fabricate cost-effective, high-efficiency, and lead-free CsSnCl3 perovskite-based high-performance SCs for a lead-free green and pollution-free environment.

Cuprous oxide (Cu2O) nanoparticles in nanofiltration membrane with enhanced separation performance and anti-fouling properties

Cuprous oxide (Cu2O) nanoparticles in nanofiltration membrane with enhanced separation performance and anti-fouling properties

Effect of pH on the electrodeposition nucleation and growth mechanism of cuprous oxide

Effect of pH on the electrodeposition nucleation and growth mechanism of cuprous oxide

Effect of Cu2O Sputtering Power Variation on the Characteristics of Radio Frequency Sputtered p-Type Delafossite CuCrO2 Thin Films

For the first time, the effect of Cuprous Oxide (Cu2O) sputtering power variation on the radio frequency sputtered Copper Chromium Oxide (CuCrO2) thin films was studied. In this work, the sputtering power of Cr2O3 was held constant at 200 W while the sputtering power of the Cu2O target was varied from 10 to 100 W. The films were subsequently annealed at 650 °C in N2 ambiance. The effects of Cu2O sputtering power variation on the structural, optical, and electrical properties of the films have been reported in this work. X-ray diffractometer (XRD) study revealed that the single-phase delafossite structure of CuCrO2 was only obtained at Cu2O sputtering power of 50 W. X-ray photoelectron spectroscopy (XPS) analysis further established the results of XRD study where Cu in 1+ oxidation state was identified in thin films obtained at 50 W of Cu2O sputtering power. The optical studies were conducted in this work on all the post-deposition annealed films in the wavelength range of 200–800 nm. The energy dispersive x-ray spectroscopy (EDS) study revealed a near stoichiometric composition ratio of 1:1.06 of Cu:Cr at% obtained in the films sputtered with 50 W of Cu2O sputtering power. The highest optical transmission of ~81% and the highest optical bandgap of 3.21 eV were observed for single-phase CuCrO2 thin films. The optical transmission and the optical bandgap were found to decrease with an increase in the Cu2O sputtering power. The electrical study performed on all the post-deposition annealed films revealed that the lowest resistivity of 0.652 Ω-cm was identified for single-phase CuCrO2 thin films obtained at 50 W of Cu2O sputtering power.

Cu2O p-type Thin-Film Transistors with Enhanced Switching Characteristics for CMOS Logic Circuit by Controlling Deposition Condition and Annealing in the N2 Atmosphere

Cuprous oxide (Cu2O) p-type thin-film transistors (TFTs) can be practically applied for complementary metal oxide semiconductor (CMOS) logic circuits, but the electrical performances are still insufficient due to high off-current and low field-effect mobility. Here, we have demonstrated Cu2O TFTs with improved field-effect mobility and low off-current through reduction of cupric oxide (CuO) impurities and dissociative Cu defects with the combination of deposition and annealing conditions. Copper oxide was deposited by radio frequency sputtering in mixed gases of argon and oxygen. After that, the deposited copper oxide was annealed at 800 °C in the tube furnace under a N2 atmosphere instead of a high vacuum condition. The fabricated Cu2O thin film had a high crystalline quality, the ratio of dissociative Cu defects decreased from 11.3 to 3.1%, and the electrical performances of the TFT including the fabricated Cu2O thin film exhibited the field-effect mobility of 1.11 ± 0.05 cm2/V·s, the on/off current ratio of 4.68 ± 0.8 × 104, and the subthreshold swing value of 3.91 ± 0.21 V dec–1. The fabricated Cu2O TFT showed a Vth shift of 3.31 V in the transfer curve under negative bias stress. Nitrogen plays a role in promoting Cu2O phase formation while it prevents CuO phase formation during the annealing process. In addition, oxygen added during sputtering increases the ratio of CuO in the copper oxide thin film and works effectively to reduce dissociative Cu defects in the annealing process. To determine the feasibility of the CMOS logic circuit, we also demonstrated the inverter with n-type indium–gallium–zinc oxide (IGZO) TFT and p-type Cu2O TFT, which showed a voltage gain of 14 at VDD = 20 V.

A biogenesis construction of CuO@MWCNT via Chenopodium album extract: an effective electrocatalyst for synaptic plasticity neurodegenerative drug pollutant detection.

Clioquinol (CLQ) is one of the most toxic halogenated neurodegenerative drugs, and its synaptic plasticity effect directly affects human health and the environment. Cupric oxide (CuO) is an ideal electrocatalyst owing to its earth-abundance, non-toxic nature, and cost-effectiveness. Since phenolate oxygen and pyridine nitrogen in CLQ act as an electron donor and pave the way for detection with Cu2+ ions in the CuO. Designing the architecture of CuO with a multi-walled carbon nanotube (MWCNT) is a sensible strategy to improve the electrochemical activity of the developed sensor. Inspired by the bio-synthesis and green processing, we have demonstrated the in-situ synthesis of CuO nanosphere-decorated MWCNT by Chenopodium album leaf extract through a sonochemical approach and explored its electrochemical sensing performance toward CLQ. The physical comprehensive characterization of prepared nanocomposite was investigated by various microscopic and spectroscopic techniques. For comparison studies, the CuO nanosphere was prepared by the same preparation process without MWCNT. Based on the physical characterization outcomes, the morphological nature of CuO was observed to be a sphere-like structure, which was decorated on the MWCNT with an average crystallite size of 16nm (± 1nm). Based on the electrochemical studies, the fabricated nanocomposite exhibits a wider linear range of 0.025-1375μM, with a minimum detection limit of 4.59nML-1 toward CLQ. The viability examination on the biological matrix obtained considerable spike recoveries.

Crystallinity Study of Cu Thin Film Deposited by Indigenously Developed DC Magnetron Sputtering Setup

AbstractThe copper thin films have a huge application in the field of material science research and they also act as a catalytic substrate which helps to deposit various carbon‐based polymers that can be used for sensors. There are several thin film development techniques available in the industries out of which magnetron sputtering technique shows some remarkable properties essential for depositing metal thin film efficiently. The main objective of this work is to develop copper thin films utilizing an indigenously designed and developed DC magnetron sputtering system. The X‐ray diffraction (XRD) pattern of the developed thin films display prominent peaks of copper (111) plane along with cuprous oxide (110), (111), and (220), respectively. This work also aims to study in detail the crystallinity of the deposited copper thin films by analyzing the XRD results for optimization.

Dielectric and Complex Impedance Spectroscopic studies of Microwave synthesized Cupric Oxide nanoparticles

Hexamethylenetetramine (HMT) capped CuO nanoparticles were synthesized by microwave assisted technique. X-ray diffraction analysis confirms the formation of monoclinic single phase of the synthesized particles. The nature of ligand bonding and an estimate of the ligand molecules on the surface of CuO particles were obtained from Fourier Transform Infrared spectroscopy and Thermogravimetric analysis, respectively. Hysteresis measurements performed at 10 and 300 K show both the core-shell nature and the impact of the ligand. Dielectric measurements were performed with a temperature variation of 10 to 325 K and a frequency variation over 126 kHz to 949 kHz range. Broad relaxation peaks, reduction of dielectric constant with size and the presence of anomalies at slight variance to the magnetic transitions observed in bulk material, show signatures of the impact of ligand. Impedance spectroscopic (IS) analysis shows the room temperature impedance to be dominated by grain boundaries and reveals core-shell type of behaviour with conducting grains and insulating grain boundaries. A schematic is proposed with the grain consisting of the ligand capped CuO clusters separated by interfaces/grain boundaries.

Hydroxyl adsorption derived reactive oxygen species from carbon paper-supported Cu2O for enhanced electrochemical glucose sensing

Engineered sensitive copper nanostructured superelectrode systems have become an important part of electrochemical sensing of glucose because of their high sensitivity, specificity, abundant natural reserves, and environmental friendliness. However, the factors affecting the electrochemical catalytic activity of glucose remain a challenging issue, which largely limits the overall electrochemical sensing performance of glucose. This paper reports the design of a carbon fiber loaded cuprous oxide nanoparticle (Cu2O NPs) electrochemical sensor with electrochemical catalytic properties for glucose oxidation. The copper grown on carbon nanofibers was subjected to cyclic redox treatment to obtain Cu2ONPs with good glucose detection ability. The detection range of the prepared Cu2ONPs was 0.05 mM − 3 mM with a sensitivity of 3 mA mM−1 cm−2. The differences in the properties of copper and cuprous oxide are analyzed in depth and the reasons for the variability are explored. By observing the electrocatalytic behavior and oxygen evolution reaction behavior of the glucose oxidation process, we hypothesized that the difference in the oxygen source provided by hydroxyl adsorption would lead to the difference in the properties of cuprous oxide and copper. Our proposed differences in the oxygen source generated by hydroxyl adsorption affecting the performance of glucose detection will provide new ideas for the design of glucose electrochemical microelectrodes.

Cu2O nanoparticles synthesized by green and chemical routes, and evaluation of their antibacterial and antifungal effect on functionalized textiles

The potential for the application of metal-containing nanomaterials at the nanoscale promotes the opportunity to search for new methods for their elaboration, with special attention to those sustainable methods. In response to these challenges, we have investigated a new method for green synthesis of cuprous oxide nanoparticles (Cu2O NPs) using Myrciaria dubia juice as an organic reductant and, comparing it with chemical synthesis, evaluating in both cases the influence of the volume of the organic (juice) and chemical (ascorbic acid) reductants, for which a large number of techniques such as spectrophotometry, EDX spectrometry, TEM, SEM, DLS, FTIR spectroscopy have been used. Likewise, the nanomaterial with better morphological characteristics, stability, and size homogeneity has been applied in the functionalization of textiles by means of in situ and post-synthesis impregnation methods. The success of the synthesis process has been demonstrated by the antimicrobial activity (bacteria and fungi) of textiles impregnated with Cu2O NPs.

Chemical, surface, and thermal studies of mixed oxides cupric oxide (CuO), lanthanum oxide (La2O3), and graphene oxide for dye degradation from aqueous solution

Mixed oxy-compositions are lately used for water treatment that might be exploited as photo-catalyst, and adsorptive materials for the disposal of water pollutants. Cupric oxide (CuO), lanthanum oxide (La2O3), and graphene oxide (GO)-based nanocomposites show an interest in water treatment applications owing to the adsorptive feature of carbon-based nanoparticles (NPs), besides low band gap of metal oxides that boosts photo-catalytic process. CuO/La2O3/GO-based nanocomposites are prepared and tested for their thermal stability, and dye removal activity. The change in nanocomposites structure upon the incorporation of CuO and La2O3 into GO nanosheets is inspected via TEM micrographs showing a decline in lanthana rod length to be 200 nm on average. Additionally, the improved roughness structure and the compact grain size appear in SEM micrographs reports CuO grain size reduction reaching an average size of 250 nm. The roughness parameters of CuO/La2O3/GO are extraordinarily heightened in which the supreme value of roughness average is 7.6 nm. Ternary nanocomposite exhibits a maximum value (85%) as a methylene blue (MB) dye removal. Based on these obtained results, the fabricated nanocomposites are recommended for water treatment due to their enriched physicochemical and morphological features as well as the better thermal stability and exerted dye removal activity.

Novel Perovskite solar cell: Incorporating CNTs and Cu2O as charge carriers transport materials for performance enhancement – Opto-electrical modelling

This contribution aims to propose novel lead-free perovskite solar cells (PSCs), that incorporate the excellent charge carriers transport (CCT) properties of both carbon nanotubes (CNTs) and cuprous oxide (Cu2O), as a mean of addressing the current challenges of today PSC technologies that are cost-effectiveness, eco-friendly and long-term stability and more efficiency. Using SCAPS software, we carried out numerical modellings by replacing functional layers of a reference PSC, by substituting TiO2 with CNT, and spiroOMeTAD with Cu2O, respectively. In this regard, we performed calculations to better appraise current–voltage and quantum efficiency characteristics, as well as means of trapping incident light. The effects of absorber coating thicknesses, doping level, and external temperature were also investigated to further improve the efficiency. The proposed architecture incorporating CNT and Cu2O demonstrated promising results: Voc = 1.00 V, jsc = 34.65 mA/cm2, FF = 72.80 %, and PCE = 25.31 %. Simulating a defects – free active coat device enables to predict a PCE = 28 %. As a first theoretical proposal of a high efficiency and stability tin-PSC, that incorporates both CNTs and Cu2O as CCT materials, performance achieved are to date the highest recorded.

Facet Dopant Regulation of Cu2O Boosts Electrocatalytic CO2 Reduction to Formate

AbstractElectrochemical carbon dioxide reduction reaction (CO2RR) using clean electric energy provides a sustainable route to generate highly‐valuable chemicals and fuels, which is beneficial for realizing the carbon‐neutral cycle. Up to now, achieving a narrow product distribution and highly targeted product selectivity over Cu‐based electrocatalysts is still a big challenge. Herein, sulfur modification on different crystal planes of cuprous oxide (Cu2O) is demonstrated, results in an improvement for formate generation to different degrees. Experimental results and density functional theory (DFT) calculations reveal that sulfur species modified on the surface of Cu2O (100) facet effectively lower the formation energy of key intermediate *OCOH for formate generation compared with Cu2O (111) facet. As a consequence, the modification of p‐Block elements over Cu‐based electrocatalysts is an effective strategy to optimize the adsorption energy of key intermediate during CO2RR, leading to a highly selective product.

Photo-induced carrier dynamics in nano-porous TiO2 electrochemically doped with cuprous oxide

In the present paper, photo-induced carrier dynamics and charge transfer processes on porous anodic TiO2, modified with Cu2O via pulse electrodeposition, are studied with steady-state and modulated photocurrent measurements in a wide range of experimental conditions. Surface composition was estimated using XPS. The obtained oxides are p-type semiconductors that effectively absorb visible light, and rates of charge transfer and recombination are strongly dependent on synthesis conditions. A tentative mechanism of photo-induced hydrogen evolution on such materials is proposed using recent simulation results from the literature and the dependence of formal charge transfer rate constant on potential.

Design and synthesis of cancer-cell-membrane-camouflaged hemoporfin-Cu9S8 nanoagents for homotypic tumor-targeted photothermal-sonodynamic therapy

Multimodal therapies have aroused great interest in tumor therapy due to their highly effective antitumor effect. However, immune clearance limits the practical application of nanoagents-based multimodal therapies. To solve this problem, we have designed hemoporfin-Cu9S8 hollow nanospheres camouflaged with the CT26 cell membrane (CCM) as a model of multifunctional agents, achieving homologous-targeted synergistic photothermal therapy (PTT) and sonodynamic therapy (SDT). Hollow Cu9S8 as photothermal agents and carriers have been obtained through sulfurizing cuprous oxide (Cu2O) nanoparticles through “Kirkendall effect”, and they exhibit hollow nanospheres structure with a size of ∼200 nm. Then, Cu9S8 nanospheres could be used to load with hemoporfin sonosensitizers, and then hemoporfin-Cu9S8 nanospheres (abbreviated as H-Cu9S8) can be further surface-camouflaged with CCM. H-Cu9S8@CCM nanospheres exhibit a broad photoabsorption in the range of 700–1100 nm and high photothermal conversion efficiency of 39.8% under 1064 nm laser irradiation for subsequent PTT. In addition, under the excitation of ultrasound, the loaded hemoporfin could generate 1O2 for subsequent SDT. Especially, H-Cu9S8@CCM NPs are featured with biocompatibility and homologous targeting capacity. When intravenously (i.v.) injected into mice, H-Cu9S8@CCM NPs display a higher blood circulation half-life (3.17 h, 6.47 times) and tumor accumulation amount (18.75% ID/g, 1.94 times), compared to H-Cu9S8 NPs (0.49 h, 9.68% ID/g) without CCM. In addition, upon 1064 nm laser and ultrasound irradiation, H-Cu9S8@CCM NPs can inhibit tumor growth more efficiently due to high accumulation efficiency and synergistic PTT-SDT functions. Therefore, the present study provides some insight into the design of multifunctional efficient agents for homotypic tumor-targeted therapy.

Synthesis of cuprous oxide via ion exchange route for photocatalytic degradation of methylene blue

Abstract Cuprous oxide (Cu2O) nanoparticles were successfully synthesized using cupric hydroxide gel as a precursor and glucose as a reductant. A well-dispersed cupric hydroxide gel was prepared by treatment of aqueous cuprous chloride with anion exchange resin. The average diameter of the Cu2O nanoparticles was 780 nm. Attenuated total reflectance Fourier transform infrared spectroscopy showed that polyethylene from the anion exchange resin was present in the Cu2O powder, explaining how the ion exchange route reduces agglomeration of the Cu2O nanoparticles. Addition of hydrogen peroxide during the photocatalytic degradation of methylene blue significantly reduced photocorrosion of the Cu2O nanoparticles. The mechanism by which hydrogen peroxide participates in the photocatalytic process and inhibits photocorrosion was investigated.

Low-voltage anodizing of copper in sodium bicarbonate solutions

The low-voltage (< 5 V) anodization of copper in aqueous solutions of sodium bicarbonate was studied for the first time. As demonstrated, this method leads to the formation of microstructures on a copper surface, that are composed of malachite (CuCO3·Cu(OH)2). Moreover, by tuning the operating conditions, i.e., applied cell voltage and electrolyte concentration, different surface morphologies can be grown. As shown by electron microscopy investigation, clusters of ribbons corrosion pits or nonuniformly located powdery precipitates are formed when the low anodizing voltage is applied. Anodization at 1.0 V in 0.4 M sodium bicarbonate solution led to the formation of a velvet-like, deep black anodic layer that covered the whole metal surface with ribbon-resembling structures. A thorough investigation of the obtained anodic layers with X-ray diffraction (XRD), X-ray adsorption (XAS), Raman, and X-ray Photoelectron Spectroscopy (XPS) uncovered the mixed crystalline-amorphous nature of the anodic copper species. Besides dominating the crystalline malachite phase, the amorphous cupric oxide was also identified. This composition offers promising features for catalytic applications, hence, low-voltage anodized copper was tested in an electrochemical CO2 reduction reaction to explore one possible application of the presented material. The current density of 4.7 mA cm−2 was registered for the selected sample.