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In this study, we have synthesized a nanostructured core–shell framework of carbon-coated copper sulfide (C@CuS) through a one-step precipitation technique. The carbon sphere template facilitated the nucleation of CuS nanostructures. The synthesized nanocomposites have demonstrated remarkable lithium-ion storage capabilities when utilized as an anode in lithium-ion batteries. Notably, they exhibit an impressive rate capability of 314 mAh g−1 at a high current density of 5000 mA g−1, along with excellent long-term cycle stability, maintaining 463 mAh g−1 at 1000 mA g−1 after 800 cycles. This superior performance is due to the core–shell architecture of the composite, where the carbon core enhances the conductivity of CuS nanoparticles and mitigates volume expansion, thus preventing capacity loss. Our study not only elucidates the significance of carbon in the construction of nano-heterojunctions or composite electrodes but also presents a practical approach to significantly boost the electrochemical performance of CuS and other metal sulfides. [ABSTRACT FROM AUTHOR]

CO2 electroreduction into liquid fuels is of broad interest and benefits reducing the energy crisis and environment burdens. CuS has been reported to be a desirable candidate for CO2 electroreduction into formate; however, its formate selectivity and stability are still far from the demands of practical application. Herein, we report CuS nanoparticles exhibiting good Faradaic efficiency of formate (about 98 %) in CO2 electroreduction and its deactivation mechanism during the reaction. The deactivation of CuS was found to be associated with the reconstruction and S loss of CuS, which deteriorates the Faradaic efficiency of formate. Combined with ionic and gas analyses, the S atom in CuS was lost in the form of H2S, SO2, and SO42−, followed by the reconstruction of CuS into copper oxides. Such a catalyst reconstruction facilitates electroreductions of CO2 and H2O, respectively, into CO and H2, etc., resulting in the degradation of catalytical performance of CO2 electroreduction into formate. This work reveals the important role of S loss and reconstruction of metal sulfide catalysts during the electroreduction reaction, which may benefit the further development of CuS‐based electro‐catalyst for CO2 electroreduction. [ABSTRACT FROM AUTHOR]

A full potential all-electron density functional method within generalized gradient approximation is used herein to investigate correlations of the electronic, elastic and thermo-electric transport properties of cubic copper sulphide and copper selenide. The electronic band structure and density of states suggest a metallic behaviour with a zero-energy band gap for both materials. Elastic property calculations suggest stiff materials, with bulk to shear modulus ratios of 0.35 and 0.44 for Cu2S and Cu2Se, respectively. Thermo-electric transport properties were estimated using the Boltzmann transport approach. The Seebeck coefficient, electrical conductivity, thermal conductivity and power factor all suggest a potential p-type conductivity for α-Cu2S and n-type conductivity for α-Cu2Se. [ABSTRACT FROM AUTHOR]

Most of the copper sulfide synthetic approaches developed until now are still facing issues in their procedure, such as long synthesis duration, high energetic consumption, and high implementation costs. This publication reports a facile and sustainable approach for synthesizing copper sulfides on a large scale. In particular, an industrial by-product of sulfur waste was used as a sulfurizing agent for copper sulfide synthesis in a water medium. The reaction was performed in the hydrothermal environment by following a novel proposed mechanism of copper sulfide formation. The investigation of morphological and optical properties revealed that the target products obtained by using waste possess the resembling properties as the ones synthesized from the most conventional sulfurizing agent. Since the determined band gap of synthesis products varied from 1.72 to 1.81 eV, the photocatalytic properties, triggered under visible light irradiation, were also investigated by degrading the methylene blue as a model pollutant. Importantly, the degradation efficiency of the copper sulfide synthesized from sulfur waste was equivalent to a sample obtained from a reference sulfurizing agent since the value for both samples was 96% in 180 min. This very simple synthetic approach opens up a new way for large-scale sustainable production of visible-light-driven photocatalysts for water purification from organic pollutants. [ABSTRACT FROM AUTHOR]

Although metal sulfides have demonstrated exceptional catalytic properties in Fenton-like reactions, little is known about the role of sulfur species in transforming highly active species responsible for degradation organics. CuS (∼12 nm) nano-capsules embedded in the biochar (CuS-BC) were prepared from copper-rich biomass, which could activate H 2 O 2 (4 mM) and completely remove tetracycline (TC) from water within 210 min. Compared with BC/H 2 O 2 /Vis system, the degradation efficiency of TC in the CuS-BC/H 2 O 2 /Vis system was improved by 14.8 times, and the utilization efficiency of H 2 O 2 was improved by 86 times. The whole degradation process of TC can be divided into two stages: quasi-first-order reaction kinetics (k obs = 0.015 min−1) and zero-order reaction kinetics (k obs = 6.457 mol/L/min). Within 90 min, H 2 O 2 is activated to produce hydroxyl radicals (OH) by surface Cu2+ on CuS and photogenerated electrons (e−) generated from CuS photoexcitation, which react immediately with surface SO 3 2− to form SO 4 −. After 90 min, CuIII-peroxo species (CuIII-O 2 2−-(SO 3 2−) n) formed by electron transfer between CuI, O 2 , and surface SO 3 2− oxidize the remaining 50 % TC through interface interaction. CuS-BC catalyst exhibits excellent photostability and suitability for actual antibiotic wastewater. Overall, this study offers mechanistic insight into the role of sulfur species in the sulfide-based Fenton reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuS/Bi 2 S 3 is prepared by a one-step hydrothermal method. • Heterojunctions are constructed between metal sulfides with narrow bandgaps. • The rate of CO generation from CuS/Bi 2 S 3 is 2.78 and 2.87 times higher than CuS and Bi 2 S 3. • Electron transmission channels promote the separation of photogenerated carriers. Enhancing the separation efficiency of photogenerated charge carriers and improving electron utilization are the primary challenges limiting the photocatalytic reduction performance. The utilization of heterojunctions to enhance the separation capability of photogenerated charge carriers, thereby increasing the product yield, is a common practice in the photocatalytic reduction of CO 2. In this work, a composite material of CuS and Bi 2 S 3 was synthesized via a one-step hydrothermal method, successfully constructing a Z-scheme heterojunction between the two materials. Under the influence of the heterojunction, CuS/Bi 2 S 3 overcame the predicament of rapid recombination of photogenerated charge carriers caused by the narrow bandgap of semiconductor materials. Facilitating the accumulation of electrons at reaction sites on CuS allows for their rapid participation in reactions, leading to increased production of CO 2 reduction products. The rate of CO generation from the photocatalytic conversion of CO 2 using CuS/Bi 2 S 3 was 108.57 μmol g−1h−1, representing an increase in the carbon monoxide yield by 2.78 times and 2.87 times compared to CuS and Bi 2 S 3 respectively, and CH 4 production of CuS/Bi 2 S 3 also increased. This study offers a new understanding of the construction of heterojunctions between metal sulfides. [ABSTRACT FROM AUTHOR]

Metal sulfide is often utilized as a catalyzed material to form colorimetric response system for some heavy metal detection. While the aggregation effect and conventional morphology limited the catalyzed efficiency. Herein, a robust method based on morphology adjustment was proposed to improve the dispersibility and catalytic performance of CuS. The results demonstrated when the solvent ratio of ethylene glycol and dimethyl sulfoxide arrived at 3:1, it displayed an optimal structure which is like a patulous flower. Meanwhile, an optimal surface binding energy (ΔE) of 120.1 kcal/mol was obtained via theoretical calculation model. The flower-like structure caused a 2-fold increase in the catalytic level. Subsequently, the CuS was employed to make colorimetric detection of Cr(VI) in water. The assay results exhibited a linear range of the Cr(VI) from 60 to 340 nM, the limit of detection was 1.07 nM. In the practical tests for Qianhu lake water, the spiked recoveries were 93.6% and 104% with the RSD of 4.71% and 3.08%. Therefore, this CuS-based colorimetric method possesses a satisfactory application prospect for the Cr(VI) determination in water. [ABSTRACT FROM AUTHOR]

The fabrication of metal sulfides heterostructure is a promising strategy for enhancing catalytic activity. Herein, the MoS 2 /CuS heterostructure was successfully grown on carbon cloth (MoS 2 /CuS/CC) through an efficient method. The SEM results confirmed that the fabricated MoS 2 /CuS/CC composites have a flake morphology, which can not only improves the surface area but also offers ample surface catalytic active sites. Particularly, the optimized MoS 2 /CuS/CC-2 electrocatalyst showed a small overpotential of 85 mV@10 mA cm−2 and exceptional long-term cycling durability for hydrogen evolution in 1 M KOH. The outstanding catalytic activity is attributed to the fact that the combination of MoS 2 with CuS can greatly enhance the charge transport rate and improve the structural stability. These results suggest that the MoS 2 /CuS/CC heterostructure is a potential electrocatalyst for hydrogen production. [Display omitted] • Flakes-shaped MoS 2 /CuS/CC electrocatalysts were successfully fabricated. • The MoS 2 /CuS/CC electrocatalysts can offer ample surface catalytic active sites. • The MoS 2 /CuS/CC electrocatalyst shows low overpotential of 85 mV@10 mA cm−2 for HER. • The MoS 2 /CuS/CC electrocatalyst presents excellent long-term cycling stability. [ABSTRACT FROM AUTHOR]

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It is highly desirable to regulate charge flow in photocatalyst for photocatalytic hydrogen reactions. In this study, a highly efficient sulfur vacancies- core–shell heterostructure photocatalyst (donoted as CdS-SV@CuS) was developed through surface modification of CdS-SV nanoparticles by CuS based on photoinduced interfacial charge transfer (IFCT). This novel photocatalyst with modulated charge transfer was prepared by hydrothermal treatment and subsequent cation-exchange reactions. The sulfur vacancies (SV) confined in CdS and the IFCT facilitate charge carriers efficient spatial separation. The optimized CdS-SV@CuS(5%) catalyst exhibited a remarkably higher H 2 production rate of 1654.53 umol/g/h, approximately 6.7 and 4.0 times than that of pure CdS and CdS-SV. The high photocatalytic performance is due to the rapid charge separation, intimate interactions between CdS-SV and CuS in the core–shell heterostructure. It is the first time adopts a facile method to construct metal sulfide core–shell structure for superior H 2 -production activity by IFCT. [Display omitted] To regulate the charge flow of the photocatalyst in photocatalytic hydrogen reactions is highly desirable. In this study, a highly efficient sulphur vacancies-CdS@CuS core–shell heterostructure photocatalyst (denoted CdS-SV@CuS) was developed through the surface modification of CdS-sulphur vacancies (SV) nanoparticles by CuS based on photoinduced interfacial charge transfer (IFCT). This novel photocatalyst with modulated charge transfer was prepared by hydrothermal treatment and subsequent cation-exchange reactions. The SV confined in CdS and the IFCT facilitate the charge carrier's efficient spatial separation. The optimized CdS-SV@CuS(5%) catalyst exhibited a remarkably higher H 2 production rate of 1654.53 μmol/g/h, approximately 6.7 and 4.0 times higher than those of pure CdS and CdS-SV, respectively. The high photocatalytic performance is attributed to the rapid charge separation, caused by the intimate interactions between CdS-SV and CuS in the core–shell heterostructure. This is the first time that a straightforward method is adopted to construct a metal sulphide core–shell structure for superior H 2 -production activity by IFCT. [ABSTRACT FROM AUTHOR]

The thermal oxidation of CuS powder was examined under flow of nitrogen and dry air using thermogravimetry/differential thermal analysis. After 473 K, the oxidation of CuS occurred as a weight loss and accompanied with two overlapped exothermic peaks. The melting temperature delayed due to the formation of oxide and sulphate on the surface of the particles. X-ray diffraction revealed that the as-prepared thin films are mixed phases of hexagonal CuS, orthorhombic Cu2S and orthorhombic CuSO4. After annealing at 573 or 773 K, the films oxidized and new orthorhombic Cu8O phase appeared, and its intensity became dominant upon increasing the temperature and time. Nanoparticles morphology was observed for as-prepared films and upon annealing the nanoparticle became more rounded and bigger. The transmittance of the as-prepared films was almost zero over the entire measured range and it increased with increase in the annealing temperature and time, whereas the reflectance decreased. Both refractive and extinction coefficient values decreased with increase in annealing temperature and annealing time, while the bandgap virtually increased. The resistivity of the as-prepared film remained nearly constant until 543 K. Above 543 K the resistivity increased sharply. Negative and positive temperature coefficients in resistivity phenomena were explored in the annealed films and they were strongly dependent on both annealing temperature and time. [ABSTRACT FROM AUTHOR]

Copper sulfide (CuS) is an attractive electrode material for batteries, thanks to its intrinsic mixed conductivity, ductility and high theoretical specific capacity of 560 mAh g−1. Here, CuS is studied as cathode material in lithium solid‐state batteries with an areal loading of 8.9 mg cm−2 that theoretically corresponds to 4.9 mAh cm−2. The configuration of the cell is LiLi3PS4[CuS (70 wt%) + Li3PS4 (30 wt%)]. No conductive additive is used. CuS undergoes a displacement reaction with lithium, leading to macroscopic phase separation between the discharge products Cu and Li2S. In particular, Cu forms a network of micrometer‐sized, well‐crystallized particles that seems to percolate through the electrode. The formed copper is visible to the naked eye. The initial specific discharge capacity at 0.1 C is 498 mAh g(CuS)−1, i.e., 84% of its theoretical value. The initial Coulomb efficiency (ICE) reaches 95%, which is higher compared to standard carbonate‐based liquid electrolytes for the same cell chemistry (≈70%). After 100 cycles, the specific capacity reaches 310 mAh g(CuS)−1. With the current composition, the cell provides 58.2 Wh kg−1 at a power density of 7 W kg−1, which is superior compared to other transition metal sulfide cathodes. [ABSTRACT FROM AUTHOR]

• Various synthetic methods for metal sulfides are introduced and compared. • Performances, merits, and flaws of metal sulfides are summarized and commented. • Layered metal sulfides, MoS 2 , WS 2 and SnS 2 , are the most promising mercury sorbents. • Effects of gas ingredients on the performances of metal sulfides are summed up. • Mercury capture mechanisms for metal sulfides are outlined and discussed. Mercury is largely emitted into the atmosphere during fossil fuel combustion or gasification, which causes a long-term contamination problem and poses great threats to human health. Currently, novel metal sulfides have been extensively investigated in capturing gaseous mercury because of their intense Hg0 affinities, large mercury uptakes, and distinguished tolerance to sulfur dioxide. This article overviews the recent progress on elemental mercury capture by diverse metal sulfides, i.e., CuS, ZnS, pyrite-phase metal sulfides, layered metal sulfides, Bi 2 S 3 and In 2 S 3. CuS and ZnS show good performances in a narrow temperature range due to the poor thermal stability and the compact crystal structure, respectively. Bi 2 S 3 and In 2 S 3 are also active in Hg0 adsorption, however, their performances are still unsatisfactory. Most pyrite-phase metal sulfides show moderate Hg0 capture abilities likely due to their compact crystal structures. Loading pyrites onto carriers or creating S vacancies in pyrite lattices seem to be feasible pathways to improve their performances. MoS 2 and WS 2 attained via molten salt method significantly outperform the ones obtained via hydrothermal method at elevated temperatures due to the production of ample sulfur variances and chemisorbed oxygen. Incorporating heteroatoms and expanding the interlayer distance by ions intercalation are effective routes to further strengthen their performances probably due to promoted electron transfer and increased accessibility of active sites, respectively. [ABSTRACT FROM AUTHOR]

Metal sulfides have received considerable attention for efficient sodium storage owing to their high capacity and decent redox reversibility. However, the poor rate capability and fast capacity decay greatly hinder their practical application in sodium‐ion batteries. Herein, an elegant multi‐step templating strategy has been developed to rationally synthesize hierarchical double‐shelled nanoboxes with the CoS2 nanosheet‐constructed outer shell supported on the CuS inner shell. Their structure and composition enable these hierarchical CuS@CoS2 nanoboxes to show boosted electrochemical properties with high capacity, outstanding rate capability, and long cycle life. [ABSTRACT FROM AUTHOR]

Abstract: Layered transition metal sulfides (LTMSs) have tremendous commercial potential in anode materials for sodium‐ion batteries (SIBs) in large‐scale energy storage application. However, it is a great challenge for most LTMS electrodes to have long cycling life and high‐rate capability due to their larger volume expansion and the formation of soluble polysulfide intermediates caused by the conversion reaction. Herein, layered CuS microspheres with tunable interlayer space and pore volumes are reported through a cost‐effective interaction method using a cationic surfactant of cetyltrimethyl ammonium bromide (CTAB). The CuS–CTAB microsphere as an anode for SIBs reveals a high reversible capacity of 684.6 mAh g−1 at 0.1 A g−1, and 312.5 mAh g−1 at 10 A g−1 after 1000 cycles with high capacity retention of 90.6%. The excellent electrochemical performance is attributed to the unique structure of this material, and a high pseudocapacitive contribution ensures its high‐rate performance. Moreover, in situ X‐ray diffraction is applied to investigate their sodium storage mechanism. It is found that the long chain CTAB in the CuS provides buffer space, traps polysulfides, and restrains the further growth of Cu particles during the conversion reaction process that ensure the long cycling stability and high reversibility of the electrode material. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of Ni 3 S 2 @CuS supercapacitor electrode material. • The Ni 3 S 2 @CuS exhibit excellent power density and energy density. • A MD simulation on Ni 3 S 2 @CuS surface to monitor the ionic movements. • The deintercalation of the K+ atoms are restricted and the intercalation of the OH– is promoted. Supercapacitors have overwhelming advantages in cycle life, charging time and power density. Metal sulfides involve reversible Faraday redox reactions, and chemical reactions occur during charge and discharge, resulting in high specific capacity of the electrode. Different from the traditional nickel foam as a current collector, in this work, vulcanized nickel foam (Ni 3 S 2) is used to further grow CuS nanosheets by hydrothermal reaction to produce new cathode material. The results show that the electrochemical properties of the electrode material Ni 3 S 2 @CuS obtained at 190 °C for 4 h reach a mass specific capacity of 967.7F/g. When assembled as a supercapacitor device, it has an energy density of 103.7 Wh/kg and a power density of 15050.3 W/kg. The coulomb efficiency of the device remains 97.4 % after 10,000 cycles of constant current charge and discharge. To deeply understand the mechanism of the capacitance increase, we carry out a molecular dynamics (MD) simulation on pure Ni 3 S 2 electrode and Ni 3 S 2 @CuS to investigate the influence of this unique structure on capacitance for the first time. We discover that the CuS tunnel on the Ni 3 S 2 electrode surface will restrict the deintercalation of K+ ions and promote the intercalation of OH–, and this phenomenon will promote the reversible redox reaction on the surface of the metal sulfides and enhance the capacitance of this pseudocapacitor. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional antitumor nanoplatform based on COFs was fabricated. • The CuS@COFs showed excellent photothermal effect, Fenton-like activity and drug loading capability. • The nanocomposites with pH-dependent fluorescence behavior were capable of cancer cell imaging. • The enhanced therapeutic efficiency was obtained from synergistic PTT/chemotherapy/CDT. Developing nanomedicines with high-performance is a promising therapeutic strategy for cancer treatment. Herein, a multifunctional nanoplatform (CuS@COFs-BSA-FA/DOX) based on copper sulfide nanoparticles engineered covalent organic frameworks (CuS@COFs) has been established for synergistic photothermal therapy (PTT), chemotherapy and chemodynamic therapy (CDT). The high photothermal effect and excellent Fenton-like catalytic activity enabled CuS@COFs to generate a new minimally invasive PTT/CDT synergistic therapy. Moreover, with the pH-dependent fluorescence behavior and the inherited mesoporous structure, the nanocomposites can also be utilized as fluorescent probes for cancer cell imaging and drug-delivery carriers to encapsulate the chemotherapeutic agent, DOX. The densely coated PEI and BSA-FA layers on the surface of CuS@COFs not only increased the cancer-targeting efficiency but also prevented the nonspecific release of DOX from CuS@COFs. The acid tumor microenvironment and near-infrared light triggered the release of DOX for chemotherapy, which simultaneously augmented the CDT efficiency of CuS@COFs. Notably, the localized hyperthermia induced by PTT can further improve the CDT efficiency of the nanoplatform, leading to a synergistic PTT/chemotherapy/CDT effect. The nanoplatform possessed the capability of cancer cell-targeted imaging and achieved better therapeutic efficacy with negligible systemic toxicity both in vitro and in vivo. Our work opens up a powerful avenue for developing multifunctional COFs-based theranostic platform and shows strong potential in practical applications. [ABSTRACT FROM AUTHOR]

• Change the structure with temperature (hexagonal, rhombohedral and monoclinic). • Increase the crystallite size due to increase temperature. • CuS change into CuO at temperature 750 °C. • Non-uniform and irregular surface morphology of the materials. • Phase shift was identified by (TGA) analysis. Present study is related to synthesize copper sulfide (CuS) nanoparticles by co-precipitation method varying calcinations temperature regimes (250,500 and 750 °C) respectively. These nanoparticles (NPs) were characterized by using various characterization techniques such as XRD, SEM, EDX, FTIR and TGA. Deviation in crystallite size, crystal structure (hexagonal, rhombohedral and monoclinic), texture coefficient and lattice parameters were identified by using XRD analysis. SEM micrograph represented that the grain size increase by increasing temperature and EDX graph shows the elemental composition of nanomaterials. Moreover, the FTIR analysis depicted the different rotational and vibrational mode attached to the surface of CuS-NPs and thermogravimetric analysis (TGA) used to identify phase shifting with varying temperature. Finally, structural analysis revealed that with increase in temperature as-synthesized. CuS transform into non-stoichiometric Cu 9 S 5 at 250 °C to CuSO 4 at 500 °C and then change into CuO (750 °C). [ABSTRACT FROM AUTHOR]

Interfacial solar steam generation is an eco-friend and energy-efficient way of harvesting solar energy for desalination and wastewater treatment. For the solar steam generation, the primary focus is to design new materials that are fully sunlight absorption, fast photothermal conversion and low heat emissivity. Here, a novel hollow copper sulfide (CuS) nanocubes with concave surface is used for rapid and efficient solar steam generation through the micro thermal management. Interestingly, the emissivity of CuS foam is as low as 0.64, whose absorption is more than 97% and strongly dependents on the structure and morphology. The unique concave structure of hollow CuS can trap the sunlight by reabsorption as well as recover radiative and convective heat loss. As a result, the CuS based generator exhibits a high evaporation efficiency of 91.5% under one sun illumination. Furthermore, the device can maintain a stable performance of solar steam generation during the cyclic seawater desalination. The novel structure design based on the micro thermal management offers a new insight into the future development of highly efficient solar steam generation. • Hollow CuS nanocubes with rough surface was synthesized. • Hollow CuS based foam has a large absorbance of 97.8% and an extremely low emissivity (~0.6). • Hollow CuS contributes to a high solar steam generation efficiency as 91.5% under 1 sun illumination. [ABSTRACT FROM AUTHOR]

• Cu metal sulfide was highly effective in the presence of K 2 S 2 O 8 and visible light. • The Orange II was completely degraded within 120 min. • Degradation efficiency of the third recycled CuS could achieve 98%. • Cu2+/Cu+ cycling enhanced the degradation of Orange II. Copper sulfide (CuS) nanoparticles were prepared at 140 °C by a simple hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer, Emmett, Teller (BET) specific surface area method. Orange II (60 mg/L) was used as the target pollutant to investigate the degradation performance of CuS and K 2 S 2 O 8 under visible light irradiation. The degradation efficiency reached 98.88% in CuS/K 2 S 2 O 8 /visible light system within 120 min, which showed very strong activity. Moreover, the catalyst also showed good stability and recycling performance for degrading Orange II. After three consecutive degradation cycles, the degradation efficiency of Orange II was found to be not less than 98%. The dye degradation mechanism was proposed as follows: Cu2+/Cu+ cycling catalyzed K 2 S 2 O 8 to produce free radicals (SO 4 −), which significantly improved the oxidation ability of CuS/K 2 S 2 O 8 /visible light system. [ABSTRACT FROM AUTHOR]

A core-shell nanorod array of TiO 2 /CuS heterostructure is achieved by coating the TiO 2 nanorods with conformal ZnS films and subsequently converting the ZnS into CuS counterparts via ion exchange. Photovoltaic devices based on the ordered heterojunctions exhibit aging-induced photoelectric conversion enhancement effect. • A highly ordered TiO 2 /CuS core-shell nanorod array is fabricated. • The CuS shell is attached to the TiO 2 nanorods by ion exchange with ZnS films. • Photovoltaic devices exhibit an enhanced efficiency when aging in air for up to 22 days. Highly ordered three-dimensional (3D) heterojunctions are attractive for optoelectronic, photovoltaic and electronic devices due to their large interfacial contact and oriented charge transport. However, 3D heterojunctions of this type have rarely been reported because of the great difficulty in constructing an ordered structure at the nanoscale. In this study, a core-shell nanorod array of TiO 2 /CuS heterostructure is achieved by coating the TiO 2 nanorods with conformal ZnS films and subsequently converting the ZnS into its CuS counterpart via ion exchange. The TiO 2 /CuS-based photovoltaic devices exhibit a gradually enhanced efficiency when aging in air up to 22 days. This is attributed to the progressive conversion from Cu deficient sulfide to CuS. This strategy could also be used to design other core-shell nanorod arrays based on metal oxide/sulfide heterojunctions. [ABSTRACT FROM AUTHOR]

Hierarchically assembled nanorod copper sulfide counter electrodes prepared via an in situ microwave‐assisted strategy which can boost the performance of quantum dot‐sensitized solar cells. The higher efficiency is assigned to the minor charge transfer impedance and higher diffusion coefficient leading to the enhanced current density and fill factor. More details can be found in article number 1801745 by Jia‐Shan Tsai, Khalilalrahman Dehvari, Jia‐Yaw Chang, and co‐workers. [ABSTRACT FROM AUTHOR]

This study describes preparation of metal sulfide counter electrodes (CEs) through one‐pot microwave‐assisted route to improve power conversion efficiency (PCE) of quantum dot‐sensitized solar cells at a lower cost. The CuS nanorods, Ni0.96S nanoparticles, and PbS nanocubes are synthesized and deposited in situ on fluorine‐doped tin oxide substrate to serve as CEs without further post‐treatment. Effects of several reaction parameters including sulfur precursor (Na2S, C2H5NS, CH4N2S), Cu concentration, reaction time, and choice of cation (Cu, Ni, Pb) on the CEs morphology, electrochemical characteristics, and PCE are studied. Furthermore, nanostructure formation and thin film growth are studied and correlated with PCE, from which morphology‐ and composition‐performance relationships can be inferred. Hierarchically assembled nanorod CuS CEs exhibit higher electrochemical stability in the S2–/Sn2– redox reaction. Together with the efficient charge transfer and higher diffusion coefficient of polysulfide redox at the electrode/electrolyte interface, deduced from electrochemical impedance spectroscopy and Tafel analyses, a PCE of 8.32% is achieved for the CuS CE. The enhanced photovoltaic performance is ascribed to the 1D CuS nanorods forming a diffusive structure which decreases charge transfer impedance and facilitates regeneration of polysulfide redox leading to a higher short‐circuit current density and fill factor. Hierarchically assembled metal sulfide thin films are prepared via an in situ microwave‐assisted strategy to serve as counter electrodes for quantum dot‐sensitized solar cells. The correlation between structural and electrochemical characteristics is studied. The improved efficiency of copper sulfide hierarchical structure is assigned to minor charge transfer impedance and higher diffusion coefficient leading to enhanced current density and fill factor. [ABSTRACT FROM AUTHOR]

CuS is a metal sulfide anode material used in constructing lithium ion batteries (LIBs) with great promise. However, its practical application is limited by rapid capacity decline, poor cycling, and rate performance. In this work, the CuS nanowire-on-nanoplate network is synthesized through an improved dealloying method under two contrasting reaction temperatures. When used as an LIB anode, the as-obtained CuS network exhibits superior cycling performance (420 mAh·g−1 retained after 100 cycles at 0.2 C). When at 3 C, it still delivers a capacity of around 350 mAh·g−1. The improved electrochemical performances of the CuS anode should be attributed to the well-designed nanowire-on-nanoplate network structure in which the introduction of nanowires improves Li storage sites, shortens Li-ion diffusion distance, enhances the conductivity of active materials, and offers multiscale spaces for buffering the volume variation. The fabrication route adopted in this paper has an important significance for developing the dealloying technique and designing more suitable anode structures for LIBs. [ABSTRACT FROM AUTHOR]