Copper Precursor Research Articles

SnO2-Cu2S nanocomposites: Structural and optical properties with enhanced photocatalytic activities for ciprofloxacin antibiotic and methylene blue dye degradation

Pharmaceutical products and industrial dyes released to water bodies have become major environmental concerns and applications of nanomaterials for their remediation have been receiving a lot of research attention in recent years. In this connection, different SnO2–Cu2S nanocomposites (NCs) have been synthesized by growing Cu2S over previously prepared SnO2 nanocrystals by taking different molarities of copper and sulphur precursors. The pure SnO2 nanocrystals have been prepared by the chemical co-precipitation method combined with calcination of the precipitated materials at 300 °C. X-ray diffraction (XRD) pattern of the pure SnO2 nanocrystals shows the formation of tetragonal crystal structure. UV–visible–NIR absorption spectrum of the pure SnO2 nanocrystals records absorption peak in the UV region, while the Tauc's plot estimates the band gap of SnO2 to be 3.93 eV. Photoluminescence (PL) and electron paramagnetic resonance (EPR) studies reveal the presence of oxygen vacancies in the pure SnO2 nanocrystals. XRD patterns of the NCs comprise of diffraction planes from both tetragonal SnO2 and monoclinic Cu2S. PL studies show presence of both oxygen vacancies and copper vacancies in the NCs. Further, presence of copper vacancies has been evidenced in the EPR signals of the NCs. The NCs show significantly enhanced photocatalytic activities for degradation of ciprofloxacin (CIP) antibiotic and methylene blue (MB) dye under simulated sunlight irradiation, which is attributed to type II heterojunction formation between SnO2 and Cu2S. The NC with the best performance as a photocatalyst degrades 96% of CIP after 120 min and 98% of MB after 210 min of light exposure.

A Simple and Fast Access to Phosphine-Substituted Copper(I)-Carbene Complexes via C=Se Bond Cleavage Reaction.

Phosphine coordinated copper(I)-N-heterocyclic carbene complexes have emerged as an efficient material in catalysis and light-emitting applications. In this study, a gentle and sustainable approach to the copper(I)-carbene phosphine complexes is reported through an efficient C=Se activation protocol. The complexes [(Py^NHC)Cu(PPh3 )2 ]X, X=BF4 (1), ClO4 (2), PF6 (3) and OTf (4); Py^NHC=3-isopropyl-1-(pyridin-2-yl)-imidazol-2-ylidene, and [(Py^NHC)Cu(PPh3 )(X)], X=Br (5) and I (6) have been synthesized by treating 1-isopropyl-3-(pyridin-2-yl)-imidazole-2-selone with corresponding copper(I) precursors and triphenylphosphine. In this synthetic strategy, N-heterocyclic carbene gets transferred from N-heterocyclic selone through a C=Se bond cleavage reaction to form copper(I) complexes within five minutes at room temperature. In addition, the mechanism responsible for the C=Se bond cleavage reaction has been fully investigated. These reactions are not sensitive to moisture and oxygen.

Voidless metal lines sintered with intense pulsed light and their applications as transparent metal-mesh electrodes

An optimal metal ink that can be sintered without void generation by intense pulsed light (IPL) was systematically formulated. This ink is a hybrid ink in which silver (Ag) nanoparticle ink and copper (Cu) precursor ink are mixed in an optimal weight ratio, and the reduced Cu fills the space between Ag nanoparticles during the sintering process. The optimization process of the ink encompasses the shape and size of nanoparticles, the type of solvent, and the mixing ratio of the Cu precursor ink. This optimized ink was filled in the engraved trenches and IPL-sintered to fabricate flexible transparent metal-mesh electrodes. If there are voids in the metal lines after IPL sintering, the metal lines may shrink under condition of high temperature and high humidity for a long time, which may deteriorate the stability of the metal electrode. It was confirmed that the hybrid ink optimized in this study hardly shrinks due to no voids inside the metal lines after IPL sintering and has excellent environmental and mechanical stability. The metal-mesh electrode produced using this ink showed superior properties compared to other competing transparent electrodes such as indium-tin oxide or Ag nanowires when used for transparent heaters and electromagnetic shielding applications.

Unraveling the Steric Link to Copper Precursor Decomposition: A Multi‐Faceted Study for the Printing of Flexible Electronics (Small Methods 4/2023)

Inside Back Cover In article number 2300038, Caroline E. Knapp and co-workers have established a link between the geometry of copper precursors and their decomposition to copper metal by single crystal X-ray diffraction investigation alongside density functional theory calculations. Precursor synthesis and their decomposition profiles are reported. Inkjet printing yielded conductive (ρ = 4.7–5.3 × 10−7 Ω m; ≈30% bulk) copper features onto paper and polyimide substrates at 125 °C and 150 °C.

Upcycling of Dyed Polyester Fabrics into Copper-1,4-Benzenedicarboxylate (CuBDC) Metal–Organic Frameworks

We report on a pathway to synthesize metal–organic frameworks (MOFs) using discarded textiles as a raw material. Discarded objects made of poly(ethylene terephthalate) (PET) could be an inexpensive and globally available source for 1,4-benzenedicarboxylic acid (H2BDC), also known as terephthalic acid, a building block of carboxylate-based MOFs. Previous studies on using discarded PET to synthesize MOFs have mainly focused on PET bottles. In contrast, we demonstrate the use of dyed polyester fabrics as a raw material. Specifically, we report on a synthesis path for copper-1,4-benzenedicarboxylate (CuBDC) utilizing disodium terephthalate (Na2BDC) as a linker and on how we obtained the linker from depolymerized polyester fabrics. To facilitate coordination between the copper ions and Na2BDC and create a localized acidic environment that favors the synthesis of CuBDC MOFs rather than metal oxide byproducts, we added acetic acid to the copper precursor solution. The drop-sized pH-controlled domain enabled the formation of CuBDC MOF crystals at room temperature and at a fraction of time shorter than traditional solvothermal methods. We confirmed the resulting MOF structures using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectroscopy, and our results were in quantitative agreement with previous reports. Furthermore, we used different copper salts as metal sources and different color-dyed polyester fabrics as linker sources, demonstrating the versatility of the proposed synthesis path. These results may open an avenue for using discarded textiles as a raw material and offer a more circular approach for managing textile waste.

Specific ion effects on copper electroplating

The main goal of this work is to open new perspectives in the field of electrodeposition and provide green alternatives to the electroplating industry. The effect of different anions (SO42-, ClO3-, NO3-, ClO4-, BF4-, PF6-) in solution on the electrodeposition of copper was investigated. The solutions, containing only the copper precursor and the background electrolyte, were tailored to minimize the environmental impact and reduce the use of organic additives and surfactants. The study is based on electrochemical measurements carried out to verify that no metal complexation takes place. We assessed the nucleation and growth mechanism, we performed a morphological characterization through scanning electron microscopy and deposition efficiency by measuring the film thickness through X-ray fluorescence spectroscopy. Significant differences in the growth mechanism and in the morphology of the electrodeposited films, were observed as a function of the background electrolyte.

Unraveling the Steric Link to Copper Precursor Decomposition: A Multi-Faceted Study for the Printing of Flexible Electronics.

The field of printed electronics strives for lower processing temperatures to move toward flexible substrates that have vast potential: from wearable medical devices to animal tagging. Typically, ink formulations are optimized using mass screening and elimination of failures; as such, there are no comprehensive studies on the fundamental chemistry at play. Herein, findings which describe the steric link to decomposition profile: combining densityfunctionaltheory, crystallography, thermal decomposition, mass spectrometry, and inkjet printing, are reported. Through the reaction of copper(II) formate with excess alkanolamines of varying steric bulk, tris-co-ordinated copper precursor ions: "[CuL3 ]," each with a formate counter-ion (1-3) are isolated and their thermal decomposition mass spectrometry profiles are collected to assess their suitability for use in inks (I1-3 ). Spin coating and inkjet printing of I1,2 provides an easily up-scalable method toward the deposition of highly conductive copper device interconnects (ρ = 4.7-5.3 × 10-7 Ω m; ≈30% bulk) onto paper and polyimide substrates and forms functioning circuits that can power light-emitting diodes. The connection among ligand bulk, coordination number, and improved decomposition profile supports fundamental understanding which will direct future design.

Dual-Functional CuO-Decorated Bi3.84W0.16O6.24/Bi2WO6 Nanohybrids for Enhanced Electrochemical Hydrogen Evolution Reaction and Photocatalytic Cr(VI) Reduction Performance

The development of dual-functional nanohybrid-based electrocatalysts/photocatalysts for producing renewable energy and removing heavy metal pollutants describes an environmentally sustainable technique to address the challenges in energy and environment applications. Herein, we adopted microwave-assisted synthesis to develop CuO-decorated Bi3.84W0.16O6.24/Bi2WO6 (CuO/biphase-BW) dual-functional nanohybrids for electrochemical hydrogen evolution reaction (HER) and photocatalytic Cr(VI) reduction applications. CuO nanoparticles with ∼50 nm were uniformly distributed on an octahedron-shaped bismuth tungstate analyzed via a high-resolution transmission electron microscope technique. Biphase bismuth tungstate optimization was meticulously controlled via the amount of copper precursor added to the reaction. Among synthesized materials, CuO1.0/biphase-BW catalysts exhibit excellent HER activity in neutral media (0.5 M Na2SO4) with a relatively low overpotential of 111 mV at a current density of 10 mA/cm2, and also it exhibits a lower Tafel slope of 237 mV/dec. Moreover, CuO1.0/biphase-BW catalyst-coated carbon cloth exhibits good conductivity and excellent electrochemical stability for 24 h. Maximum photocatalytic reduction of aqueous Cr(VI) was achieved on the CuO1.0/biphase-BW catalyst. It is worth mentioning that the tremendous activity of the synthesized electrocatalyst/photocatalyst can be ascribed to the formation and electronic interaction of CuO with biphase Bi3.84W0.16O6.24/Bi2WO6, thus increasing its surface-active sites and charge transfer. Our work provides a facile and effective way to engineer dual-functional nanohybrids for efficient water splitting in a neutral medium and reducing toxic (Cr(VI)) metal.

Heteroleptic Copper Complexes as Catalysts for the CuAAC Reaction: Counter-Ion Influence in Catalyst Efficiency

A series of nine cationic heteroleptic aryl-BIAN-copper(I) (BIAN = bis-iminoacenaphthene) complexes with the general formula [Cu((E-C6H4)2BIAN)(PPh3)2][X] (E = p-Me, p-iPr, o-iPr; X = BF4, OTf, NO3) 1X–3X were synthesized and fully characterized using several analytical techniques, including NMR spectroscopy and single-crystal X-ray diffraction. Except for complexes 2BF4 and 3BF4, which were already reported in our previous works, all remaining complexes are herein described for the first time. Two different strategies were used for the preparation of the complexes: complexes bearing BF4− or OTf− counter-ions (1BF4, 1OTf, 2OTf, and 3OTf) were obtained using the appropriate copper(I) precursors [Cu(NCMe)4][BF4] or [Cu(NCMe)4][OTf], whereas for derivatives 1NO3–3NO3, [Cu(PPh3)2NO3] was used. Their activity as catalysts for the copper azide-alkyne cycloaddition (CuAAC) was assessed alongside other high activity, previously reported Cu(I) complexes. Comparative studies to determine the influence of the counter-ion and of the aryl substituents were performed. All complexes behaved as active catalysts under neat reaction conditions, at 25 °C and in short reaction times without requiring the use of any additive, with complex 2NO3 being the most efficient derivative, along with other NO3−-bearing complexes.

Structural Diversity, XAS and Magnetism of Copper(II)-Nickel(II) Heterometallic Complexes Based on the [Ni(NCS)6]4- Unit.

The new heterometallic compounds, [{Cu(pn)2}2Ni(NCS)6]n·2nH2O (1), [{CuII(trien)}2Ni(NCS)6CuI(NCS)]n (2) and [Cu(tren)(NCS)]4[Ni(NCS)6] (3) (pn = 1,2-diaminopropane, trien = triethylenetetramine and tren = tris(2-aminoethylo)amine), were obtained and characterized by X-ray analysis, IR spectra, XAS and magnetic measurements. Compounds 1, 2 and 3 show the structural diversity of 2D, 1D and 0D compounds, respectively. Depending on the polyamine used, different coordination polyhedron for Cu(II) was found, i.e., distorted octahedral (1), square pyramidal (2) and trigonal bipyramidal (3), whereas coordination polyhedron for nickel(II) was always octahedral. It provides an approach for tailoring magnetic properties by proper selection of auxiliary ligands determining the topology. In 1, thiocyanate ligands form bridges between the copper and nickel ions, creating 2D layers of sql topology with weak ferromagnetic interactions. Compound 2 is a mixed-valence copper coordination polymer and shows the rare ladder topology of 1D chains decorated with [CuII(tren)]2+ antennas as the side chains attached to nickel(II). The ladder rails are formed by alternately arranged Ni(II) and Cu(I) ions connected by N2 thiocyanate anions and rungs made by N3 thiocyanate. For the Cu(I) ions, the tetrahedral thiocyanate environment mixed N/S donor atoms was found, confirming significant coordination spheres rearrangement occurring at the copper precursor together with the reduction in some Cu(II) to Cu(I). Such topology enables significant simplification of the magnetic properties modeling by assuming magnetic coupling inside {NiIICuII2} trinuclear units separated by diamagnetic [Cu(NCS)(SCN)3]3- linkers. Compound 3 shows three discrete mononuclear units connected by N-H…N and N-H…S hydrogen bonds. Analysis of XAS proves that the average ligand character and the covalency of the unoccupied metal d-based orbitals for copper(II) and nickel(II) increase in the following order: 1 → 2 → 3. In 1 and 2, a weak ferromagnetic coupling between copper(II) and nickel(II) was found, but in 2, additional and stronger antiferromagnetic interaction between copper(II) ions prevailed. Compound 3, as an ionic pair, shows, as expected, a spin-only magnetic moment.

Synthesis of copper nano/microparticles via thermal decomposition and their conversion to copper oxide film.

Copper nano/microparticles were synthesized in octadecene at 290 °C by thermal decomposition method. Copper acetate monohydrate, stearic acid, and 1-octadecanol were used as copper precursor, capping and mild reducing agents, respectively, at the synthesis. Borosilicate glass substrates submerged into the reaction solution during the synthesis were coated by copper nano/microparticles. Thermal decomposition and coating techniques were combined in this study. Copper nano/microparticles were thoroughly characterised via X-ray powder diffraction, X-ray photoelectron, Raman, and attenuated total reflectance-Fourier transform infrared spectroscopies, and scanning and transmission electron microscopies. The average minimum Feret's diameter of these synthesized copper particles was measured as ~87 ± 19 nm. Copper nano/microparticles were converted to copper oxide nano/microparticles by applying heat treatment at 250 °C. The phase composition of copper oxide nano/microparticles was determined by reference intensity ratio analysis. The energy gap of copper oxide nano/microparticles was determined as ~2.33 eV by using Tauc's method. Their band gap PL emission was observed at ~2.15 eV.

Cu/SiO2 CATALYSTS OBTAINED BY CATIONIC ADSORPTION FROM DIFFERENT PRECURSOR SALTS

In this work the effect of different copper precursor salts (acetate, nitrate, sulfate) on the physicochemical characteristics of Cu/SiO2 catalysts is studied. The catalysts were prepared by the cationic adsorption method and analyzed by several characterization techniques (TGA, DSC, FTIR, XRD, AAS, SEM-EDS, N2-sorptometry and TPR). The results showed that the copper acetate precursor generated highly dispersed nano-sized copper oxide species on the silica surface, while the copper nitrate precursor leaded to bulk-type copper oxide strongly interacting with the silica, and the copper sulfate precursor did not decompose completely during the catalyst preparation. Besides, the acetate precursor produced the highest copper content, due to lower acidity of its solution, which generated a higher density of negative charge on the silica surface and a higher affinity for cupric ions. In conclusion, the great influence of the nature of the precursor salt on the physicochemical characteristics of silica-supported copper catalysts is established.

Ultrasonic Assisted Facile Synthesis of CuO Nanoparticles and Used as Insecticide for Mosquito Control

The present study deals with the fabrication of copper oxide nanoparticles with high purity via ultrasonic assisted chemical precipitation method. Synthesized CuO nano-mosquitocides rely on the polyvinyl pyrrolidine (PVP) as stabilizing agent. Synthesized CuO nanoparticles were confirmed via UV-vis spectroscopy, scanning electron microscope, X-ray diffraction, EDX, Fourier-transform infrared and SEM mapping studies. The crystallite size from XRD studies revealed around 13.44 nm. The synthesized CuO nanoparticle was further assessed for mosquito larvicidal activity against south-urban mosquito larvae Aedes aegypti. The synthesized CuO nanoparticle displayed significant activity against Aedes aegypti with the LD50 value of 43.95 μg/mL than precursor copper chloride dihydrate and control permethrin with the LD50 value of 94.31 and 72.44 μg/mL.

Novel effects of copper precursors on the adsorption and desorption of elemental mercury over copper-based sulfides: Performance, mechanism, and kinetics

BackgroundMore Hg0 adsorption onto the spent CuSx/TiO2N [Cu(NO3)2 as the Cu precursor] in the presence of O2 and SO2 and less Hg0 desorption from it occurred simultaneously after the regeneration, which was likely related to the formation of new Cu precursor (CuSO4 from the sulfation of CuO) before the sulfuration. Methods: The effects of two different Cu precursors [i.e., Cu(NO3)2 and CuSO4] on the performance of CuSx/TiO2 for Hg° capture were investigated by comparing the kinetic parameters of Hg0 adsorption and desorption. Significant findings: CuSO4 generally retained its intact structure after the calcination due to its strong heat stability, but Cu(NO3)2 was decomposed into CuO and Cu2O; therefore, both more active S22− that oxidized the physically adsorbed Hg0 to HgS and less S0 that provided the unstable adsorption sites were formed on CuSx/TiO2-S (CuSO4 as the precursor) during the sulfuration than CuSx/TiO2N. Meanwhile, the amount of unsaturated coordination sites onto CuSx/TiO2-S for Hg0 physical adsorption was significantly larger than that onto CuSx/TiO2N. Therefore, not only did Hg0 adsorb more onto CuSx/TiO2-S, but it also desorbed less from CuSx/TiO2-S. In consequence, Cu-based sulfides derived from the CuSO4 precursor were more suitable for Hg° capture from smelting flue gas.

Beneficial Effect of β‐Cyclodextrin Assisted Synthesis of CuO/Hydroxyapatite Catalyst in Toluene Oxidation

AbstractTwo hydroxyapatite supported CuO (10 wt% Cu) catalysts were prepared using the wet impregnation method via the conventional process and with the addition of native β‐cyclodextrin using Cu(NO3)2.3H2O as copper precursor and adopting a ratio of β‐cyclodextrin to copper of 0.1. After the impregnation step, the materials were dried at 80 °C and calcined in flowing dry air at 400 °C. The copper supported materials were characterized in the dried state and after calcination by means of conventional methods including X‐ray diffraction, TG‐MS, H2‐TPR‐MS, Raman spectroscopy, UV‐vis‐DR, ToF‐SIMS and XPS. It was found that β‐cyclodextrin hasd a profound impact on the final properties of the catalysts, both in terms of reducibility and dispersion of active species. It is suggested that at the early stages of the calcination, some hydroxyl groups of the β‐CD units in close contact with Ca2+ of hydroxyapatite could play the role of spacers between the copper‐based entities thus minimizing the aggregation process of the CuO nanoparticles. Finally, these copper oxide catalysts prepared from β‐cyclodextrin were able to oxidize toluene more efficiently than the conventional catalyst. The copper oxide particles generated by the thermal decomposition of Cu2(OH)3(NO3) were smaller than those formed with copper nitrate alone and exhibited a higher reducibility, two key determinants for VOC total oxidation on transition metal oxides.

Effect of Deposition Temperature on the Properties of Copper-Zinc Sulphide Thin Films using Mixed Copper and Zinc Dithiocarbamate Precursors

The influence of deposition temperatures on the structural, elemental, optical and electrical properties was investigated. The Rutherford backscattering (RBS) and scanning electron microscopy (SEM) were used to measure the elemental and morphological properties of the films. The RBS confirms that the stoichiometry was controlled by the deposition temperatures with a thickness that ranged between 51.00 to 63.00 nm. SEM data of the deposited films show different morphologies with several grains that increased with deposition temperature. Optical characterization shows that the films exhibited a direct transition with an energy gap that varies from 1.79 to 2.10 eV. For copper-zinc sulphides (CZS) film deposited at 470 ᴼC, the maximum electrical conductivity was 7.38 × 10-2 (Ω.cm)-1and minimum electrical resistivity was 1.35 × 101 (Ω.cm). The results confirm the possibility of using copper and zinc dithiocarbamate precursors in depositing high-quality CZS thin films with comparable properties.

Intrafibrillar Dispersion of Cuprous Oxide (Cu2O) Nanoflowers within Cotton Cellulose Fabrics for Permanent Antibacterial, Antifungal and Antiviral Activity.

With increasingly frequent highly infectious global pandemics, the textile industry has responded by developing commercial fabric products by incorporating antibacterial metal oxide nanoparticles, particularly copper oxide in cleaning products and personal care items including antimicrobial wipes, hospital gowns and masks. Current methods use a surface adsorption method to functionalize nanomaterials to fibers. However, this results in poor durability and decreased antimicrobial activity after consecutive launderings. In this study, cuprous oxide nanoparticles with nanoflower morphology (Cu2O nanoflowers) are synthesized in situ within the cotton fiber under mild conditions and without added chemical reducing agents from a copper (II) precursor with an average maximal Feret diameter of 72.0 ± 51.8 nm and concentration of 17,489 ± 15 mg/kg. Analysis of the Cu2O NF-infused cotton fiber cross-section by transmission electron microscopy (TEM) confirmed the internal formation, and X-ray photoelectron spectroscopy (XPS) confirmed the copper (I) reduced oxidation state. An exponential correlation (R2 = 0.9979) between the UV-vis surface plasmon resonance (SPR) intensity at 320 nm of the Cu2O NFs and the concentration of copper in cotton was determined. The laundering durability of the Cu2O NF-cotton fabric was investigated, and the superior nanoparticle-leach resistance was observed, with the fabrics releasing only 19% of copper after 50 home laundering cycles. The internally immobilized Cu2O NFs within the cotton fiber exhibited continuing antibacterial activity (≥99.995%) against K. pneumoniae, E. coli and S. aureus), complete antifungal activity (100%) against A. niger and antiviral activity (≥90%) against Human coronavirus, strain 229E, even after 50 laundering cycles.

Effect of Reducing Agent on Characteristics and Antibacterial Activity of Copper-Containing Particles in Textile Materials.

Textile materials modified with copper-containing particles have antibacterial and antiviral properties that have prospects for use in healthcare. In the study, textile materials were saturated with copper-containing particles in their entire material volume by the absorption/diffusion method. The antibacterial properties of modified textile materials were confirmed by their inhibitory effect on Staphylococcus aureus, a Gram-positive bacterium that spreads predominantly through the respiratory tract. For the modification, ordinary textile materials of various origins and fiber structures were used. Technological conditions and compositions of modifying solutions were established, as well as the most suitable textile materials for modification. To assess the morphological and physical characteristics of copper-containing particles and the textile materials themselves, X-ray diffraction, a scanning electron microscope, and an energy-dispersive X-ray spectrum were used. In modified textile samples, XRD data showed the presence of crystalline phases of copper (Cu) and copper (I) oxide (Cu2O). On the grounds of the SEM/EDS analysis, the saturation of textile materials with copper-containing particles depends on the structure of the textile materials and the origins of the fibers included in their composition, as well as the modification conditions and the copper precursor.

Effect of copper precursors on CO oxidation catalyzed by CuO-CeO2 prepared by solvothermal method

In this paper, the CuO–CeO2 catalyst was prepared by a direct solvothermal method. The effects of different copper salt precursors (copper nitrate, copper acetate, copper sulfate) on the catalytic performance of the prepared catalyst for CO oxidation were investigated. The physical and chemical properties of the prepared catalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, N2 physical adsorption, inductively coupled plasma-atomic emission spectrometry (ICP-AES), X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption analysis of CO (CO-TPD), in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs), and temperature-programmed reduction with H2 (H2-TPR). The results show that the CuO–CeO2 catalyst prepared with copper acetate as precursor (CC-A) exhibits the best catalytic activity for CO oxidation at low temperatures, with T50 and T90 values of 62 and 78 °C respectively, which is mainly attributed to its large specific surface area, pore volume, CO adsorption capacity, and large amount and strong reactivity of surface oxygen. However, the CuO–CeO2 catalyst prepared with copper nitrate as precursor (CC–N) displays better stability and resistance to water or CO2 poisoning than CC-A.

Ag coated CuS core/shell nanoparticles to harness the full Vis-NIR spectrum for photocatalysis

Photocatalysis has broad applications in pollution and related environmental issues. CuS shows broad absorption (600–1000 nm) and has application in dye photodegradation for toxic pollutants. In this study, CuS nanoparticles were synthesized using two copper precursors: CuCl2 and Cu(OAc)2. These nanoparticles were further coated with Ag using AgNO3 under light irradiation. The pure CuS and CuS/Ag core–shell nanoparticles were characterized by XRD, FESEM, UV–vis absorption, photoluminescence, and XPS. The results confirmed the formation of core–shell nanostructured CuS/Ag. The photocatalytic activity tested using methyl-blue dye. The enhanced degradation with core–shell nanoparticles shows their potential application as a catalyst for dye degradation.