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Compared with traditional water electrolysis, electrolysis of seawater has larger resources and a brighter future. However, seawater contains more elements that have greater corrosive effects on electrodes; especially chloride ions (seawater contains more chloride ions) have the greatest impact. The existence of the corrosion problem creates greater difficulties in electrolyzing seawater, further limiting the efficiency of the electrocatalyst for electrolysis of seawater. In this paper, we report a Mn-doped Ni 2 P/Cu 3 P as an environmentally friendly monofunctional electrode for seawater electrolysis, which was made by a simple hydrothermal phosphatization operation method. The experimental results show that Mn-doped Ni 2 P/Cu 3 P presents overpotential of only 161 mV for oxygen evolution reaction (OER) at iR compensation of 90 and a current density of 10 mA cm−2. It has a small Tafel slope (25.15 mV dec−1) and a large capacitance (9.58 mF cm−2 on 1 × 1 nickel foam), which exceeds most reported oxygen evolution activities of non-precious metal-based electrocatalysts for electrolysis of alkaline seawater. The performance of Ni 2 P/Cu 3 P was probably significantly enhanced due to Mn doping by some characterization means. Through Density functional theory (DFT) analysis, it is known that the doping of Mn gives a large enhancement in the adsorption energy of water when Ni 2 P/Cu 3 P is electrolyzed with seawater. This paper provides train of thought for the exploration of excellent electrocatalysts for electrolysis of alkaline seawater. The experimental results show that Mn-dopedNi 2 P/Cu 3 P present overpotential of only 161 mV at i-R compensation of 90 for oxygen evolution reaction in alkaline seawater. [Display omitted] • Mn-doped Ni 2 P/Cu 3 P electrodes was synthesized for the first time through hydrothermal processes. • The overpotential of Mn-doped Ni 2 P/Cu 3 P electrode is only 161 mV at 10 mA cm−2 for OER. • The doping of Mn gives a large enhancement in the adsorption energy of water. [ABSTRACT FROM AUTHOR]

The present paper reports a remote carbon‐to‐carbon boryl migration via an intramolecular 1,4‐B/Cu shift, which establishes an in situ stereospecific electrophilic trap on the alkene moiety. The synthetic application is developed to prepare functionalized cyclopentenes by means of a palladium‐catalyzed regioselective intramolecular coupling that completes a strategic cyclopropanation and generates valuable structural bicyclic systems. The mechanism is characterized by DFT (density functional theory) calculations which showed that the 1,4‐migration proceeds through an intramolecular, nucleophilic attack of the copper‐alkyl moiety on the boron atom bonded to the C(sp2), leading to a 5‐membered boracycle structure. The computation of the 1,3‐ and 1,4‐B/Cu shifts is also compared as is the impact of the endo‐ or exocyclic alkene on the reaction kinetics. [ABSTRACT FROM AUTHOR]

The insulating gas and contacts in the arc extinguishing chamber of high‐voltage circuit breakers are the focus of research. In practical applications, the gas may react with the surface of the contacts. In this paper, C5F10O environmental friendly insulating gas, which has one of the potential alternatives, is selected as the research object. The compatibility of C5F10O and its decomposition products with CuW contacts was studied. This article uses the Dmol3 program based on density functional theory. The adsorption energy, transfer charge, and density of electronic states of C5F10O and selected typical decomposition products on the Cu (111) surface and Cu‐W surface were calculated, respectively. It was found that the original CuW metal properties were not changed before and after adsorption. The carbonyl O atom in C5F10O is easily adsorbed on the top of the Cu (111) surface, forming a stable CuO bond, which belongs to chemical adsorption. The interaction of the other three adsorption sites is weaker than that of the top site adsorption, which belongs to physical adsorption. C5F10O exhibits more active charge transfer and forms active W‐O chemical bonds when adsorbed on CuW surfaces than SF6. C5F10O has poorer compatibility with CuW alloy than SF6. C2F4 and C3F6 in the decomposition gas are chemically adsorbed on the Cu‐W surface. CO2, CF4, C2F6, and C3F8 do not form chemical bonds on the CuW surface. The adsorption stability of COF2 is weaker than that of CF4, C2F6, and C3F8. Compared with SF6 adsorption, the compatibility of C5F10O and CO2 on the surface of CuW contact is inferior to that of Cu contact. CF4, C2F6, C3F8, and COF2 in the decomposition gas can be compatible with the surface of the CuW contact. C2F4 and C3F6 cannot be well compatible with the surface of CuW contacts. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Seawater is one of the richest hydrogen sources around our environment, so it has a lot of advantages to decompose and produce hydrogen. However, considering that chloride ions in seawater have a strong corrosive action on the electrode. Therefore, the design and exploration of highly effective and antiseptic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) electrocatalysts were studied. It's worth noting that Cu 2 S@Ni 3 S 2 /NF is engaged as a difunctional electrode in this study, which drives a current density of 10 mA cm−2 with requiring overpotentials of only 78 mV and 170 mV, and highlights its significant selectivity of OER and HER. The results show that the increased activity of Cu 2 S@Ni 3 S 2 /NF electrode can be assigned to the synergistic catalysis of (211) and (110) crystal faces, as well as the transfer and the increase of the number of active sites caused by lattice defects. The results of density functional theory show that Cu 2 S material has optimal free energy of the adsorbed states for H, indicating that the introduction of Cu 2 S promotes the kinetics of the reaction. The introduction of Ni 3 S 2 material greatly improves the conductivity of Cu 2 S@Ni 3 S 2 /NF electrode. This paper proposes novel insights into the exploration of environmentally friendly and corrosion resistant difunctional catalysts for seawater splitting. Cu 2 S@Ni 3 S 2 /NF is used as a difunctional catalyst in this study, which provides a current density of 10 mA cm−2 with required overpotentials of only 130 mV and 170 mV, and highlights its significant selectivity of OER and HER. [Display omitted] • Cu 2 S@Ni 3 S 2 electrodes was synthesized for the first time through hydrothermal processes. • The overpotential of Cu 2 S@Ni 3 S 2 electrode is only 130 m V at 100 mA cm−2 for OER. • Density functional theory analysis demonstrates that the Ni 3 S 2 material presents optimal free energy for H. [ABSTRACT FROM AUTHOR]

Copper-based catalysts have demonstrated notable efficacy in facilitating methanol conversion and hydrogen yield at low temperatures. Given the straightforward and cost-effective nature of the process, further investigation into this area is merited. This article provides a summary of the progress made in the development of copper-based catalysts for hydrogen production through methanol steam reforming. The catalytic performance of conventional Cu/ZnO/Al 2 O 3 catalysts can be exceeded by utilizing specific catalyst formulations and preparation procedures, which are characterized by their intricate structural and chemical properties. The studies about MSR mechanism have also been integrated. The realm of DFT research encompasses an examination of the monatomic systems, which have garnered significant attention in contemporary times. Furthermore, this paper presented potential avenues for future research on copper-based catalysts in the context of MSR. We believe that the forthcoming research will concentrate on the design, preparation, and molecular mechanism of copper-based catalysts that exhibit high stability, high activity, and low CO selectivity. [Display omitted] • Various copper-based catalysts for MSR are reviewed. • Research hotspots are given via disassembling the components of catalysts. • Synthesis processes for outstanding catalytic performances are underlined. • The MSR mechanisms are reviewed in detail. • DFT Studies considering experimental results are emphasized. [ABSTRACT FROM AUTHOR]

The influence of defects on graphene quantum capacitance has been widely studied using various modeling approaches and in particular the fixed-band approximation (FBA). However, computational models do not yield results in agreement with experiments and can rarely account for the effect of the metallic substrate. They typically predict capacitance values an order of magnitude higher than experiment. In this paper we assess the capacity of the recently developed interfacial capacitance model (ICM) based on density functional theory (DFT) calculations, to investigate the impact of three point-like defects on graphene capacitance. The modeled defects are single-vacancy, double-vacancy, and Stone-Wales; all defective graphene structures are modeled on Cu(111) substrate. The impact of the density of single-vacancy defects on the capacitance was carefully analyzed. The computations demonstrate that the ICM can predict capacitance of graphene on a metallic substrate in agreement with experiment even in the case of the existence of defect. This suggests that ICM can be generalized for assessing graphene capacitance and interfacial capacitance regardless of morphology of the surface. The results ranged from 1.692 μ F c m − 2 to 1.872 μ F c m − 2 for defective models, compared with 1.73 μ F c m − 2 of pristine model which is in agreement with experiment. Various defective cases were analyzed using density of states, projected density of states, electrons isosurfaces, and structural parameters. The charge separation triggered by defects can be correlated with the increase in capacitance as long as no chemical bonding is triggered by the defect between copper and graphene. • The interfacial capacitance model's (ICM) generality to estimate the capacitance. • The interaction of the point-like defects in graphene with the underlying substrate. • The charge separation's role and its impact on the capacitance. • Capacitance is estimated to slightly increase in the presence of point-like defects. • Capacitance is estimated to decrease when chemical bonds exist with the substrate. [ABSTRACT FROM AUTHOR]

A new type of copper cysteamine photosensitizer, Cu-Cy: Cu 3 Cl (SR) 2 (R = CH 2 CH 2 NH 2), was reported and later, there was another experimental report of Cu-Cy synthesis with other halogen elements (Cu-Cy-X, X = F, Br, and I), these later group of cysteamines contained Cl as an impurity. To realize the full potential applications of these cysteamines as photosensitizers, it is imperative to fundamentally understand the effect of Cl on the stability and optical properties of Cu-Cy-F/Br/I. In this paper, the stability of Cl-doped Cu-Cy-X (X = F, Br, and I) and their electronic and optical properties pertaining to their application as photosensitizers were investigated by using density functional theory (DFT). It was found that mixing Cu-Cy-Br and Cu-Cy-I with Cl increased their thermodynamic stability as well as made the materials mechanically harder. In addition, mixing halogens in Cu-Cy rendered a significant impact on their optical properties, namely the mixing affected Cu-Cy's deexcitation to their ground states during the photosensitizing process. In addition, it was found that after the initial photoexcitation within these Cu-cysteamines, the intersystem crossing can take place due to spin–orbit coupling from the Cu atoms. [Display omitted] • Mixing Cl with Br and I in Cu-Cy increases the thermodynamic stability of Cu-Cy. • Cl in Cu-Cy-X2 (X2 = F, Br, and I) makes the material mechanically hard. • Çu-Cy structures with higher contents of I are kinetically more stable. • Intersystem crossing occurs due to spin-orbit coupling. • Cu-Cy-X is initiated at a lower UV region comparing to mixed halogen Cu-Cy. [ABSTRACT FROM AUTHOR]

Due to the serious consequences of the accumulation of heavy metals in organisms throughout the aqueous phase, the treatment of heavy metal pollution has received extensive attention. Porous geopolymer adsorbent (PGA) has been proposed as a promising remover of heavy metal ions due to its production convenience, low cost, and large surface area. However, it is easy to be broken under water impact. Besides, compared to some other adsorbents, the heavy metal ions capacity of PGA needs to be enhanced. In this paper, PGA with 1000 kg/m3 density was directly prepared based on solid waste including fly ash and slag at room temperature. Nano-silica (NS) was added to improve material strength. The compressive strength of PGA with 2 % NS addition increases up to 63.5 % compared with the material without NS addition, and the removal rate of Cu2+ goes to 78.4 % under this condition. Although the filling effect caused by NS addition is not beneficial for the adsorption ability improvement, the molecular dynamics simulation results confirm that the physical adsorption ability upward is mainly caused by the more Natrium-Aluminate-Silicate-Hydrate formation due to the decreasing Ca/Si ratio. Compared with Calcium-Aluminate-Silicate-Hydrate, Natrium-Aluminate-Silicate-Hydrate has a higher physical adsorption ability due to the evenly distributed electropositive region known from the density functional theory analysis, which contributes to PGA adsorption capacity from the outside environment. [Display omitted] • Porous geopolymer adsorbent is a promising remover of heavy metal ions. • NS addition improves adsorbent strength by 63.5% avoiding the adsorbent from being broken. • NS addition leads to more NASH formation contributing to adsorption ability improvement. • The rate of Cu2+ removed by porous geopolymer adsorbent in this study reaches 78.4%. • The evenly distributed electropositive region of NASH contributes to a stronger adsorption ability. [ABSTRACT FROM AUTHOR]

The chemical mechanical polishing (CMP) process of Through Silicon Via (TSV) tantalum (Ta) base barrier layer is essential for 3D packaging and 2.5D packaging of IC chips. However, achieving high tantalum layer removal rates and an adjustable selection ratio of tantalum to copper (Cu) remains a major challenge. The effect of ethylenediamine etramethylenephosphonic acid (EDTMPA) as a complexing agent on the chemical-mechanical polishing of tantalum base barrier layer of TSV was studied in this paper. When the concentration of EDTMPA is 2 wt%, the removal rates of Cu and Ta are 561 Å/min and 1533 Å/min, respectively, and the rate selection ratio of Ta and Cu reaches 2.73:1. Through electrochemical experiments, X-ray photoelectron spectrometer (XPS), Scanning electron microscope (SEM) and Density Functional Theory (DFT) simulation, the mechanism of EDTMPA promoting the removal of Cu and Ta was revealed. It was found that EDTMPA molecules reacted with Cu and Ta and oxides to form mass complexes, which promoted the corrosion of Cu and Ta. By comparing the surface quality before and after polishing with atomic force microscopy, it is found that the surface roughness of Cu decreases from 1.4 nm before polishing to 0.164 nm after polishing, and the surface roughness of Ta decreases from 1.74 nm before polishing to 0.142 nm after polishing. The results show that EDTMPA can effectively improve the surface quality of TSV tantalum barrier layer after polishing. [Display omitted] [ABSTRACT FROM AUTHOR]

• Secondary and tertiary carbamates are prepared in high efficiency in an unprecedentive strategy. • Active transition metal-functionalized MOFs are synthesized via an in situ -grown protocolunder solvent-free mechanochemical conditions. • Both aminesand aniline are well tolerated. The solvent-free synthesis of MOF represents a promising and environmentally benign protocol. This paper outlines a green one-pot mechanochemical method for the synthesizing of UiO-66 in the absence of solvent, along with the implantation of three different metals (Cu, Ni, and Pd) into the defect sites. The materials have proven to be effective catalysts in the transformation between azidocarbonate and amines/anilines in moderate to excellent isolated yields (up to 94%), exhibiting better advantages compared with the exiting methodologies. More interestingly, Cu and Ni exhibited very good catalytic performance towards primary and secondary amines, respectively. It also should be noted that high yield was still observed after six cycles. Our work presents a novel and straightforward strategy for the preparation of secondary and tertiary carbamates in an unprecedented fashion, greatly enriched the toolbox for the synthetic community. Moreover, the combination of experimental studies and density functional theory (DFT) calculations gave more insight and evidence for the mechanism. Accompanied by the advantages of the effective and recyclable catalyst, the broad substrate scope, good functional group tolerance, and excellent reaction yields made the established method attractive in heterogeneous catalysis and the carbamates synthesis. [Display omitted] [ABSTRACT FROM AUTHOR]

Neutral (l -histidinato)(l -glutaminato)copper(II) [Cu(His)(Gln)] has been established as the most abundant ternary copper(II) amino acid compound of the exchangeable copper(II) pool in blood plasma. The experimental studies of Cu(His)(Gln) and bis(glutaminato)copper(II) [Cu(Gln) 2 ] in solutions did not specify their complete geometries. To determine the geometries, this paper investigates the conformers, energy landscapes, and a structure–magnetic parameters relation of Cu(Gln) 2 and Cu(His)(Gln) by the density functional theory (DFT) calculations. We assume a glycine-like coordination of Gln (other coordination patterns are dismissed because of steric reasons), and three His in-plane copper(II) binding modes. The conformational analyses are performed in the gas phase and implicitly modeled aqueous solution. The reliability of the DFT relative electronic and Gibbs free energies of the Cu(His)(Gln) conformers is confirmed by benchmarking against the corresponding energies obtained by the domain-based local pair natural orbital coupled-cluster method with singles, doubles, and perturbative triples [DLPNO-CCSD(T)]. Several cis - and trans -Cu(His)(Gln) conformers with His in the histaminate-like and glycine-like modes have low Gibbs free energies, and the greatest estimated metal-binding affinities. The DFT-calculated magnetic parameters of the low-energy conformers reproduce best the experimental electron paramagnetic resonance parameters measured in aqueous solutions for trans - and cis -Cu(Gln) 2 conformers having two oxygen atoms (either from Gln or water molecules) at the apical positions, and Cu(His)(Gln) conformers having His in the histaminate-like mode with an apically placed carboxylato oxygen atom. The predicted conformational flexibility of His‑copper(II)-amino acid compounds may be connected with their physiological abundance, and the role in copper(II) exchange reactions in blood plasma. Density functional calculations of conformers, energy, and magnetic parameters of bis(l -glutaminato)copper(II) and (l -histidinato)(l -glutaminato)copper(II) in aqueous solution reveal a conformational flexibility of the ternary compound, which may be connected with its physiological abundance. The analyzed structure-magnetic parameters relationship locates the low-energy aqueous conformers that best reproduce the experimental parameters. [Display omitted] • Compounds of Cu(II) with l -glutamine (binary) and l -histidine (ternary) are studied. • The equilibrium structures are predicted by density functional calculations. • The conformational analyses are performed in gas phase and aqueous solution. • The low-energy solution conformers and coordination modes are predicted. • The magnetic parameters of the low-energy conformers match the experimental ones. [ABSTRACT FROM AUTHOR]

[Display omitted] • The deep and rapid removal of arsenic from high acid copper electrolyte was achieved. • No loss of copper, nickel and sulfuric acid in the electrolyte when removing arsenic. • The addition of precipitant does not affect copper electrolytic refining. • The precipitant can be recycled and has good arsenic removal effect. Copper electrolytes generally contain high concentrations of arsenic (As), which is very harmful in copper electrolytic production. In this paper, a zirconium salt, which selectively precipitated arsenic, was added to the electrolyte to realize rapid and efficient arsenic removal. The effects of zirconium salt addition, the reaction temperature, reaction time and different electrolytes on arsenic removal were systematically investigated, the concentration equilibrium curves for As and Zr were established at different temperatures, the effects of residual zirconium ions on copper electrolysis were evaluated, and a theoretical study of the arsenic removal process was carried out. The results showed that with the optimal conditions for arsenic precipitation, 85.41 % of the As was removed from the industrial electrolyte, and the As concentration in the electrolyte was decreased to 1.41 g/L. Regeneration of the precipitates was achieved in NaOH solutions, and the regenerated precipitates exhibited efficient As removal. The As–Zr reactions followed a third-order kinetics model, and the apparent activation energy was 36.42 kJ/mol. Furthermore, the As–Zr reaction pathway, transition state structure and microscopic valence bonding changes were investigated with density functional theory (DFT). This research provides a promising method for processing copper electrolyte with high contents of As. [ABSTRACT FROM AUTHOR]

The energy barrier of C C coupling on Cu 13 @TiO 2 and Cu 20 @TiO 2 is lower among all the Cu n @TiO 2 with n=3 to 20. [Display omitted] • Cu n metal cluster is mainly bonded to the O atom of the TiO 2 (1 0 1) surface, and they are all stable with negative adsorption energies. • The interface position between the Cu n cluster and the TiO 2 surface is important for the coupling reaction of CO*+CO*→COOC*. • The coupling reaction between CO* and CO* to form COOC* on the large Cu n cluster (n ≥ 10) is easier than that on the small Cu n cluster (n ≤ 8). • The lowest energy of two CO* coupling forming COOC* occurs on Cu 13 @TiO 2 and Cu 20 @TiO 2. Cu n @TiO 2 nanocatalytic materials are widely used in experiments to catalyze the reduction of CO 2 to hydrocarbon fuels and oxygenated alcohols. However, due to the complexity of the coupling reaction of the Cu n @TiO 2 catalyst to form key C C bonds to C2 products, it is unclear. In this paper, the density functional theory (DFT) is employed to systematically study the influence of the size of Cu n clusters on the C C bond formation with the Cu n cluster supporting on the TiO 2 surface. It was discovered that the adsorption of Cu metal clusters of different sizes on TiO 2 was primarily determined by the bonding of TiO 2 oxygen atoms. Subsequently, in the CO*+CO* → COOC* coupling reaction on each different Cu n cluster size, we found that the active site was the interface position, when the Cu n cluster showed a three-dimensional configuration, with the increase of the Cu cluster, that is, the coordination number increased, the activation energy barrier gradually decreased, and when the coordination of Cu cluster reached saturation, the coupling energy barrier size also stabilized. This work provides new sight of the size of co-catalyst in the CO 2 reduction reaction and may guide to synthesis higher efficiency co-catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-atom cadmium sulfide (TM − CdS) doped with 13 transition metals (TM) were constructed by DFT. • The structural stability and mechanism of ammonia synthesis were calculated. • Based on stability, number of transferred electrons, and NRR activity, Fe − CdS, Mo − CdS, and Ru − CdS are more advantageous than others. • The limiting potential for the occurrence of NRR on the Mo − CdS structure is − 0.261 V, which is the lowest. • Detailed reaction path and energy barrier of NRR by 13 transition metal doped CdS were discussed. Single-atom catalysts with ultra-high atomic utilization and selectivity show great potential in the production of NH 3 through electrocatalytic nitrogen reduction reaction (NRR). In this paper, 13 single-atom cadmium sulfide (TM − CdS) doped with different transition metals (TM) (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Ru, Ag) were constructed separately using a density functional theory approach to calculate the structural stability and the reaction mechanism of catalytic ammonia synthesis. hree systems, Fe − CdS, Mo − CdS, and Ru − CdS, were screened out from the 13 doped metal 0structures on the basis of the computational results. The above three systems have more stable structures, can transfer more charge to activate N 2 molecules, and exhibit better NRR catalytic activity. The limiting potential NRR on the Mo − CdS structure is only − 0.261 V, which is lower than that of Fe − CdS (−0.353 V), Ru − CdS (−0.461 V) and CdS (−2.124 V). This work will be of great value of designing and employing the doped single-atom catalysts for efficient electrolytic nitrogen reduction reaction. [ABSTRACT FROM AUTHOR]

The hydrophobic mechanism of MHCODT onto malachite surface during froth flotation with Hallimond tube. [Display omitted] • 5-methyl hexyldithiocarbamate-1,3,4-oxadiazole-2-thione (MHCODT) was prepared. • MHCODT provided effective flotation separation of malachite from calcite and quartz. • MHCODT was chemisorbed on malachite surfaces by forming Cu S and Cu N bonds. • The MHCODT-Cu(I) surface complex hydrophobized malachite particles. In this paper, 5-methyl hexyldithiocarbamate-1,3,4-oxadiazole-2-thione (MHCODT) was synthesized for the first time and introduced as a flotation collector in malachite flotation separation process from quartz and calcite. During the micro-flotation experiment, it was found that MHCODT showed stronger flotation ability and selectivity for malachite than conventional collector octyl hydroxamic acid (OHA), and achieved effective separation and enrichment of malachite. Measurements of contact angles, ζ-potentials and UV spectra demonstrated that MHCODT specifically adhered to the surface of malachite rather than quartz and calcite. Then, FTIR and X-ray photoelectron spectroscopy (XPS) demonstrated that Cu of malachite surface combined with S and N of MHCODT to form MHCODT-Cu(I) complexes, accompanied by the reduction of divalent Cu. The result of density functional theory (DFT) method indicated that the C S bonds and N H bonds in oxadiazole thione and the dithiocarbamate groups were the chemical reaction center. Based on the above test results, the adsorption models of MHCODT-Cu+ and MHCODT-Cu2+ were proposed. [ABSTRACT FROM AUTHOR]