Amorphous Copper Research Articles

The effect of the composition of hepatoprotective action on biochemical and morphostructural changes in the body of laying hens under thermal stress

To reduce the negative effects of hyperthermia on the body of farm animals and poultry, various drugs and feed additives are currently used. Which do not have sufficiently adaptogenic and antitoxic properties. We studied the effect of a hepatoprotective composition consisting of dried live yeast, amorphous silicon dioxide, propylene glycol, calcium propionate, ascorbic acid, manganese, copper and zinc chelates, methionine and choline chloride on the variability of biochemical and morphological parameters of the body of laying hens under temperature stress. It was simulated by increasing the air temperature in a building where laying hens were kept from 18.0 ± 1.0 °C to 28.0 ± 1.0 °C for 48 hours. Due to hyperthermia, changes in biochemical and morphofunctional parameters were observed in the tissues and organs of birds. The obtained values of the biochemical parameters of blood serum in the birds of the control group indicated the intensity of the adaptive capabilities of their body. A complex of morphological changes confirmed a violation of protein metabolism and the regenerative-compensatory process. Pathological changes in the structure of the duodenum, characteristic of catarrhal-necrotic duodenitis, were identified. The stress reaction was also reflected in the condition of the heart muscle, in which an inflammatory process developed against the background of granular dystrophy of cardiomyocytes. The results of biochemical studies of blood serum in birds of the experimental group indicated an increase in the anti-stress response to a temperature stimulus under the influence of the studied composition (tendency to increase glucose and calcium, increase alkaline phosphatase activity by 47.4 %). The introduction of a hepatoprotective composition into the diet of laying hens during periods of temperature stress did not lead to disruption of the structure of tissues and organs, preserving cellular metabolic mechanisms. The

Impact of amorphous structure on CO2 electrocatalysis with Cu: A combined machine learning forcefield and DFT modelling approach

Amorphous materials hold significant promise for enhancing electrocatalytic CO2 reduction (CO2R) performance, but their intricate structures present challenges in understanding their behaviour. We present a computational investigation combining machine learning force fields and DFT calculations to explore amorphous copper (Cu) as a potential catalyst for the CO2R to C1 and C2 products. Our study reveals that amorphous Cu surfaces, compared to crystalline counterparts, offer a wider range of coordination sites, leading to a multitude of active centres for CO2 adsorption. Notably, some investigated surfaces spontaneously activate CO2, demonstrating their potential for efficient conversion. Furthermore, the intermediates of the CO2R on these surfaces exhibit enhanced stability, translating to lower overpotentials and improved selectivity. This work paves the way for further research and development in using amorphous Cu-based catalysts for sustainable CO2 conversion technologies, offering significant potential for mitigating climate change.

Photoelectrocatalytic Water Splitting by Conformal Copper‐Oxide on Hematite Nanostructures: Dependence on Surface‐States

AbstractUnderstanding the pivotal role of surface co‐catalysts is paramount in the strategic design of forthcoming photoelectrodes. However, the nuanced impacts of co‐catalysts remain elusive, particularly in promoting the water oxidation reaction on hematite, especially in connection to surface states denoted as S1 (higher energy) and S2 (lower energy). For this purpose, we tailored two isomorphous hematite nanoarrays with a thin layer of amorphous copper oxide (CuOx), composed of a blend of Cu(I) and Cu(II) species, via a soft electrodeposition technique. Remarkably, we discovered that in pristine hematite (α‐Fe2O3), the S2 state played a pivotal role in activating the CuOx ad‐layer for water oxidation. At lower external biases (approximately 0.9–1.1 VRHE), CuOx served as charge reservoir in equilibrium with the S2 state. Notably, beyond 1.1 VRHE, where the high‐energy holes of the S1 state became available, CuOx was activated indirectly through the equilibrium with the S2 state, and a pronounced enhancement in photocurrent was observed. Conversely, in the case of Ti‐doped hematite (Ti : α‐Fe2O3) devoid of the S2 state, the presence of CuOx resulted in a decline in charge transfer efficiency. Instead of facilitating water oxidation, CuOx adversely affected the S1 surface sites and reduced the charge carrier density in Ti : α‐Fe2O3.

Electrochemical reduction of CO to liquid C2+ with high Faradaic efficiency of amorphous CuO hybrid material wrapped in carbon and silica

Carbon monoxide (CO) is well recognized as one of the key intermediates for carbon dioxide (CO2) electrolytic reduction to C2+ products, which has been a hot research field recently. Developing an efficient catalyst that focuses on achieving C-C coupling is highly important for the production of C2+ products. In the present work, we present a feasible approach via the combination of electrostatic assembly and the hydrothermal method of coupling silicon polyanions and copper salts to build an amorphous copper hybrid material wrapped in carbon-silica, denoted as CuO@C-SiO2-X (where X means preparation temperature), as an efficient electrocatalyst for carbon monoxide reduction mainly to liquid C2+ products. The CuO@C-SiO2-X catalyst demonstrated excellent electrocatalytic activity and selectivity, especially to C2+ liquid products with the highest Faradaic efficiency of 81.5%. Additionally, the catalyst showed good stability. The presence of carbon enhanced electronic conductivity, and the silica protected the amorphous CuO from aggregation into crystalline structures. The present work not only provides an efficient catalyst for CO electrocatalytic reduction to liquid C2+ chemicals but also offers a protocol for building Cu-based catalysts with high selectivity to C2+ products in CO reduction.

Boosting Electrochemical Reduction of Nitrate to Ammonia by Constructing Nitrate-Favored Active Cu-B Sites on SnS2.

The electrochemical reduction of nitrate to ammonia is an effective method for mitigating nitrate pollution and generating ammonia. To design superior electrocatalysts, it is essential to construct a reaction site with high activity. Herein, a simple two-step method is applied to in situ reduce amorphous copper over boron-doped SnS2 nanosheets(denoted as aCu@B-SnS2-x. DFT calculations reveal the combination of amorphous copper and B-doping strategy can construct Cu-B active twins and introduce sulfur vacancies on the surface of the inert SnS2, the active twins can efficiently adsorb nitrate and forcibly separate oxygen atoms from nitrate under the assistance of the exposed Sn atom, leading to strong nitrate adsorption. Benefiting from this, aCu@B-SnS2-x exhibited an ultrahigh NH3 FE of 94.6% at -0.67V versus RHE and the highest NH3 yield rate of 0.55mmolh-1mg-1 cat (9350µgh-1mg-1 cat) at -0.77V versus RHE under alkaline conditions. Besides, aCu@B-SnS2-x is confirmed to remain active after various stability tests, suggesting the practicality of utilizing aCu@B-SnS2-x in industrial applications. This work highlights the feasibility of enhanced nitrate-to-ammonia conversion efficiency by combining the doping method and amorphous metal.

Amino acid-mediated amorphous copper sulphide with enhanced photothermal conversion efficiency for antibacterial application

Pathogenic bacteria in daily life, such as Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), often seriously affect human life and health. The extensive use of antibiotics has led to the emergence of drug-resistant bacteria, so it is urgent to develop efficient and non-drug-resistant sterilization methods. Here, we use small-molecule cysteine (Cys) as an auxiliary agent to synthesize spherical porous amorphous CuS-Cysteine (CuS-C) nanoparticles, which have good dispersion in aqueous solutions, and explore the reaction mechanism of Cys-induced CuS synthesis. The synthesized composite nanomaterials have strong near-infrared light absorption ability and efficient photothermal conversion ability and can effectively ablate pathogenic bacteria under the irradiation of an 808 nm laser. In addition, antibacterial experiments showed that CuS-C composites had no bactericidal effect without near-infrared light, but they had a good photothermal bactericidal effect on S. aureus and E. coli under radiation conditions. Considering the simple synthesis process, strong photothermal conversion ability, low cost, and suitability for large-scale production, CuS-C nanocomposites, as a promising antibacterial material, will provide a feasible scheme for the treatment of drug-resistant pathogens.

Indoor and outdoor photovoltaic modules Performances based on thin films solar cells

This paper summarizes the electrical and thermal characterizations of thin film PV modules based on amorphous triple junctions (3J: a-Si) and Copper Indium Selenide (CIS) thin film solar cells. Tests are operated in outdoor exposure and under natural sunlight of URAER located in Saharan region of Ghardaïa (Algeria) as specific desert climate environment, characterized by high irradiation and temperature levels as well as ENEA-Portici located in Naples (Italy) as Mediterranean site. PV modules performance evaluation was performed according to international standard as diagnostic test of data manufacturer. We used the thermal infrared analysis to detect the homogeneity mapping temperature of solar cells in the PV module. Data acquired from Environmental Operating Conditions (EOC) was converted into solar module output characteristics at Standard Test Conditions (STC) by using three method suggested by A.J. Anderson and G. Blaesser as well as the equations already standardized as IEC 60891. Then, based on the investigation results of the conversion equations, these methods of translation are distinguished by the type of solar cell technology and the application range. A difference between the tests in situ and in natural environment exists, attributed to various factors but mainly to the mismatch between the spectral responses of PV module and the reference solar cell.

Molecular Dynamics Study of the Devitrification of Amorphous Copper Nanoparticles in Vacuum and in a Silver Shell

The process of the devitrification of copper nanoparticles in vacuum and in a silver shell during heating was studied using a molecular dynamics simulation. The results show that there is an inverse relationship between the particle diameter and devitrification temperature. As the size of the particles decreases, the temperature at which devitrification occurs increases due to a higher fraction of atoms near the interface. The presence of a silver shell leads to a significant increase in the devitrification temperature of the copper nanoparticles. For the considered particle sizes, the difference between the devitrification temperatures without a shell and with a shell ranged from 130 K for copper particles with a diameter of 11 nm to 250 K for 3 nm particles. The mechanisms of the nucleation of a crystalline phase in particles in vacuum and in a silver shell are significantly different. In the first case, crystalline nuclei are predominantly formed near the surface, while in the second case, on the contrary, they are formed within the particle’s volume.

Amorphous copper(II)-cyanoimidazole frameworks as peroxidase mimics for hydrogen sulfide assay

Metal-organic frameworks with hierarchical porosities and exposed active sites are promising for ideal enzyme mimics. In this work, we developed a simple and feasible air oxidation strategy to prepare amorphous Cu(II)-cyanoimidazole frameworks (aCu(II)-CIFs) using CuI as the metal source in dimethylsulfoxide. Benefiting from coordination unsaturation and hierarchical porosities, aCu(II)-CIFs exhibit inherent peroxidase-mimic activity for rapid colorimetric reaction of 3,3′,5,5′-tetramethylbenzidine (TMB). aCu(II)-CIFs were utilized to develop a colorimetric platform for specific H2S assay in the range of 0.6–30 μM, achieving a limit of detection (LOD) of 0.071 μM. Structural collapse of aCu(II)-CIFs and subsequent generation of stable CuS particles, along with reducibility of H2S, are likely responsible for suppressing TMBox conversion. The proposed method successfully detected H2S in real water samples, with a relative standard deviation (RSD) lower than 8.4%. This contribution is expected to offer unique insights into the amorphization mechanisms of MOFs and their potential applications.

Interface characteristic of Zr-based metallic glass and copper by laser pulse welding

The crystallization behavior of amorphous alloys during welding is more complex than that of traditional metals. In this paper, the Zr-based amorphous alloy and copper crystals were welded by pulsed laser butt welding method, the crystallization behavior of the amorphous alloy/crystalline metal welding interface is deeply studied. The results show that Zr2Cu and Zr2Ni crystal phases appear at the interface between Zr based amorphous alloy and copper, and a Cu rich region is formed at the amorphous side of the interface. A small amount of Zr, Ni, Ti diffuses to the Cu side, forming ZrO2, TiO2, CuO and other oxides on the surface of the sample. These oxides will cause changes in the voltage potential at the interface.

Introduction of oxygen vacancies and amorphous layers into copper vanadium oxide for better lithium ion battery performance

The introduction of protective layers and defects in electrodes is an effective strategy to improve the reversible capacity and cyclic stability of batteries. In the present work, using a cuprous oxide template, copper vanadate oxide with a diverse morphology is synthesized by an in-situ etching process followed by calcination. Moreover, oxygen vacancies and an amorphous copper vanadium oxide shell are successfully introduced into moniliform Cu3V2O8 (denote as m-Cu3V2O8@aCVO) by changing the template morphology from Cu2O polyhedrons to polypyrrole-coated Cu2O nanowires. The electrochemical performances of the samples are evaluated using a lithium half-cell as the anode. The m-Cu3V2O8@aCVO manifests superior rate performance (428 mAh g−1 at 5 A g−1) and cyclic stability (938 mAh g−1 is obtained after 200 cycles), the microstructure is well-maintained after cycles. The Li-storage mechanism of the electrode changed from diffusion-controlled to pseudo-capacitance-controlled due to the introduction of oxygen vacancies. The excellent electrochemical performance could be attributed to the introduction of oxygen vacancies and the protective layer, which improves the pseudo-capacitance and structural durability of the electrode during the cyclic process. This work provides new insight into the design of high-performance anodes for energy storage applications.

Micron-Scale Fabrication of Ultrathin Amorphous Copper Nanosheets Templated by DNA Scaffolds.

Two-dimensional (2D) amorphous materials could outperform their crystalline counterparts toward various applications because they have more defects and reactive sites and thus could exhibit a unique surface chemical state and provide an advanced electron/ion transport path. Nevertheless, it is challenging to fabricate ultrathin and large-sized 2D amorphous metallic nanomaterials in a mild and controllable manner due to the strong metallic bonds between metal atoms. Here, we reported a simple yet fast (10 min) DNA nanosheet (DNS)-templated method to synthesize micron-scale amorphous copper nanosheets (CuNSs) with a thickness of 1.9 ± 0.4 nm in aqueous solution at room temperature. We demonstrated the amorphous feature of the DNS/CuNSs by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Interestingly, we found that they could transform to crystalline forms under continuous electron beam irradiation. Of note, the amorphous DNS/CuNSs exhibited much stronger photoemission (∼62-fold) and photostability than dsDNA-templated discrete Cu nanoclusters due to the elevation of both the conduction band (CB) and valence band (VB). Such ultrathin amorphous DNS/CuNSs hold great potential for practical applications in biosensing, nanodevices, and photodevices.

Amorphous copper cobalt carbonate hydroxide prepared by SILAR on copper foam for non-enzymatic glucose sensing

Amorphous copper cobalt carbonate hydroxide prepared by SILAR on copper foam for non-enzymatic glucose sensing

Stabilizing the interfacial Cu0-Cu+ dual sites toward furfural hydrodeoxygenation to 2-methylfuran via fabricating nest-like copper phyllosilicate precursor

Furfural hydrodeoxygenation (HDO) to 2-methylfuran (2-MF) is one of the most momentous routes in upgrading of biomass platform molecules, where the most universally employed active metal—Cu often suffers from thermal sintering and poor stability in spite of its brilliant effect on the activation of carbonyl. In this study, we designed a highly active and stable Cu/SiO2 nanocatalyst by fabricating nest-like nanotubes (CuSi-N) through a two-step method: preparation of amorphous copper phyllosilicate through ammonia evaporation, followed by a further hydrothermal crystallization with the assistance of P123. Notably, the CuSi-N catalyst gives a 2-MF space–time yield of 46.6 mmol·gcat−1·h−1, which is much larger than CuSi-A prepared by the conventional ammonia-evaporation method. A combination study (Raman spectra, TEM, H2-TPR, XPS, CO-DRIFTS and NH3-TPD) verifies that the nest-like precursor enhances the CuOx-SiO2 interaction, which results in a promoted Cu+ abundance as well as thermal stability of the active sites. In situ FTIR spectra of adsorbed molecules, coupled with density functional theory calculations, prove that Cu+ sites are responsible for the adsorption and activation of both furfural (FAL) and intermediate furfuryl alcohol (FOL) while Cu0 sites account for H2 dissociation. This work discloses the significance of the synergy effect of Cu0-Cu+ dual sites of Cu/SiO2 catalysts which could be employed for the other HDO reactions in the upgrading process of biomass.

Highly distributed amorphous copper catalyst for efficient ammonia electrosynthesis from nitrate

Electroreduction of nitrate to ammonia, instead of N2, is beneficial toward pollution control and value-added chemical production. Metallic catalysts have been developed for enhancing ammonia evolution efficiency from nitrate based on the crystalline state of the catalyst. However, the development of amorphous metallic catalysts with more active sites is still unexplored. Herein, a highly distributed amorphous Cu catalyst exhibiting an outstanding ammonia yield rate of 1.42 mol h−1 g−1 and Faradaic efficiency of 95.7%, much superior to crystallized Cu, is demonstrated for nitrate-reduction to ammonia. Experimental and computational results reveal that amorphizing Cu increases the number of catalytic sites, enhances the NO3− adsorption strength with flat adsorption configurations, and facilitates the potential determining step of *NO protonation to *NHO. The amorphous Cu catalyst shows good electrochemical stability at − 0.3 V, while crystallization weakens the activity at a more negative potential. This study confirms the crystallinity-activity relationship of amorphous catalysts and unveils their potential-limited electrochemical stability.

Effects of Copper Content on the Microstructural, Mechanical and Tribological Properties of TiAlSiN–Cu Superhard Nanocomposite Coatings

The effects of the Cu content on the microstructural, mechanical and tribological properties of the TiAlSiN–Cu coatings were investigated in an effort to improve the wear resistance with a good fracture toughness for cutting tool applications. A functionally graded TiAlSiN–Cu coating with various copper (Cu) contents was fabricated by a filtered cathodic arc ion plating technique using four different (Ti, TiAl2, Ti4Si, and Ti4Cu) targets in an argon-nitrogen atmosphere. The results showed that the TiAlSiN–Cu coatings are a nanocomposite consisting of (Ti,Al)N nano-crystallites (~5 to 7 nm) embedded in an amorphous matrix, which is a mixture of TiOx, AlOx, SiOx, SiNx, and CuOx phase. The addition of Cu atoms into the TiAlSiN coatings led to the formation of an amorphous copper oxide (CuOx) phase in the coatings. The maximum nanohardness (H) of ~46 GPa, H/E ratio of ~0.102, and adhesion bonding strength between coating and substrate of ~60 N (LC2) were obtained at a Cu content ranging from 1.02 to 2.92 at.% in the TiAlSiN–Cu coatings. The coating with the lowest friction coefficient and best wear resistance was also obtained at a Cu content of 2.92 at.%. The formation of the amorphous CuOx phase during coating growth or sliding test played a key role as a smooth solid-lubricant layer, and reduced the average friction coefficient (~0.46) and wear rate (~10 × 10−6 mm3/N·m).

Crystalline-amorphous core-shell copper vanadate coralline as anode material for high-performance lithium-ion battery

Constructing electrode materials with core-shell structures is considered an effective strategy to enhance the electrochemical performance of lithium-ion batteries (LIBs) anode. Herein, a novel amorphous copper vanadium oxide coated crystalline copper vanadates was designed and synthesized through a template transformation route. The copper vanadates showed a three-dimension coralline morphology assembled by nanoparticles. When applied to the LIBs anode, the as-prepared electrode exhibited a large reversible capacity (967 mAh g−1), superior rate performance (390 mAh g−1 at 5 A g−1), and cycle stability (98.2% retention after 200 cycles). This enhanced lithium storage was related to the synergistic effect of the amorphous buffer layer and abundant oxygen vacancies that could buffer volume expansion and promote the pseudo-capacitance behavior.

Amorphous HKUST-1 Nanoparticles and Their Modification for Highly Sensitive Dengue Virus Immunosensor

In this work, the amorphous HKUST-1 nanoparticles (aHKUST1) and copper hydroxide nanosheet (Cu(OH)2 NS) were successfully prepared by involving diethanolamine (DEOA) and were applied as an immunosensor to detect dengue virus (DENV-3) NS1. 35 wt% of DEOA was found to not only provide a base environment but also act as a crystal modifier for the HKUST-1. The DEOA changes the crystallinity and morphology of HKUST-1 into amorphous and highly uniform nanoparticles, respectively. In addition, the Cu(OH)2 NS was obtained by immersing the aHKUST1 NPs in water for 6 h. The aHKUST1 NPs and Cu(OH)2 NS were functionalized as a matrix material to immobilize the DENV-3 monoclonal antibody. The immunosensor was fabricated by dropping the matrix on the surface of a screen-printed carbon electrode (SPCE). The immunosensor performances were evaluated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) technique in detecting DENV-3 NS1 antigen at the concentration in the range of 0.001–100 ng ml−1. As immunosensor aHKUST1 NPs and Cu(OH)2 NS can detect the antigen down to 1.64 pg ml−1 and 2.07 pg ml−1, respectively. The amorphous nature of HKUST-1 is believed to provide many active sites that can enhance electrocatalytic activities thereby improving immunosensor performance.

Hollow-structured amorphous Cu(OH)x nanowires doped with Ru for wide pH electrocatalytic hydrogen production

Developing efficient and stable catalysts for electrocatalytic hydrogen evolution reaction (HER) with low overpotential is the key point to realizing large-scale hydrogen commercialization. Herein, Ru doped amorphous hollow copper hydroxide nanowires on copper foam (Ru-Cu(OH)x/CF) is prepared by surface chemical oxidization and following solvothermal process. The hollow 3D nanowire structure can provide abundant accessibility active sites, promote electrolyte in filtration and facilitate gas diffusion in the process of the electrochemical reaction. Then, the as-synthesized Ru-Cu(OH)x/CF electrocatalyst exhibits impressive electrocatalytic performance for HER with 45, 80 and 50 mV to drive 10 mA cm−2 in 1.0 M KOH, 1.0 M phosphate-buffered saline (PBS) and 0.5 M H2SO4, respectively, with remarkable long-term stability. Moreover, sustainable energies can power the two-electrode setup with amounts of hydrogen generation. The strategy may be particularly beneficial to explore simple synthesis and high-performance catalysts for HER.

Biodegradable Amorphous Copper Iron Tellurite Promoting the Utilization of Fenton-Like Ions for Efficient Synergistic Cancer Theranostics.

The major hurdles of chemodynamic therapy (CDT) are nondegradability and low-efficiency utilization of chemodynamic agents, and intracellular glutathione (GSH)-induced rapid scavenging of hydroxyl radicals (•OH). Here, a biodegradable a-CFT@IP6@BSA agent is reported for efficient cancer therapy by encapsulating amorphous copper iron tellurite nanoparticles (a-CFT NPs) into inositol hexaphosphate (IP6) and bovine serum albumin (BSA). The biggest merits of this agent are the GSH responsive degradation and amorphous structure, allowing the tumor-specific release of plenty of Cu+ ions and their high-efficiency utilization for •OH production via the Fenton-like reaction. Besides, the released Cu+ ions can deplete the intracellular GSH and thereby protect •OH from scavenging, greatly improving the CDT efficiency. Further, it is found that the a-CFT@IP6@BSA NP treatment down-regulates the levels of glutathione peroxidase 4 and BCL-2, indicating GSH depletion-associated ferroptosis and IP6-induced apoptotic death of cancer cells. Utilizing the T1/T2 dual-modal magnetic resonance imaging capability, the a-CFT@IP6@BSA NPs are demonstrated with excellent in vivo anticancer efficiency and have great potential for imaging-guided cancer treatment.