Search

Highlights: Erythrocyte-like CuS microspheres were encapsulated in ultrathin polyaniline (PANI) layer coating. PANI swollen by electrolytes stabilizes solid electrolyte interface layer and benefits the ion transport and charge transfer at the PANI/electrolyte interface. Multi-functional PANI coating ensures an outstanding comprehensive performance for sodium-ion storage. The latest view suggests the inactive core, surface pulverization, and polysulfide shuttling effect of metal sulfides are responsible for their low capacity and poor cycling performance in sodium-ion batteries (SIBs). Whereas overcoming the above problems based on conventional nanoengineering is not efficient enough. In this work, erythrocyte-like CuS microspheres with an elastic buffering layer of ultrathin polyaniline (PANI) were synthesized through one-step self-assembly growth, followed by in situ polymerization of aniline. When CuS@PANI is used as anode electrode in SIBs, it delivers high capacity, ultrahigh rate capability (500 mAh g−1 at 0.1 A g−1, and 214.5 mAh g−1 at 40 A g−1), and superior cycling life of over 7500 cycles at 20 A g−1. A series of in/ex situ characterization techniques were applied to investigate the structural evolution and sodium-ion storage mechanism. The PANI swollen with electrolyte can stabilize solid electrolyte interface layer, benefit the ion transport/charge transfer at the PANI/electrolyte interface, and restrain the size growth of Cu particles in confined space. Moreover, finite element analyses and density functional simulations confirm that the PANI film effectively buffers the volume expansion, suppresses the surface pulverization, and traps the polysulfide. [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]

• A novel nonlinear coupled model for dynamic attributes of a thin-walled anisotropic pre-twisted beam is formulated. • Large flapping, lagging and torsion displacements are considered (geometric nonlinearity). • Comparative impact of nonlinearity on dynamics of two structural tailoring techniques, CAS and CUS are exploited. • Influence of degree of nonlinearity on the accuracy is demonstrated. • Impact of geometric nonlinearity for different ply and pre-twist angles is analysed and presented meaningfully. It is essential to understand the nonlinear free vibration behaviour of a thin-walled composite structure as they find their applications in harsher environments prone to large deformations. Further, these structures made of fibrous materials, have directional properties for different fibre orientations resulting in a diversified and a complex nonlinear behaviour. In this regard, present work provides a comprehensive mathematical formulation on nonlinear vibration of pre-twisted thin-walled anisotropic box beam. The mathematical model is derived as coupled (flap-lag-extension-torsion) model considering shear deformation and green's strain tensor for large displacements in order to study the influence of nonlinear couplings on the dynamic behaviour. The derived energy equations are presented depending on degree of nonlinearity. These nonlinear equations those derived are nondimensionalized and solved with in the frame work of energy method using classical Ritz approximation. An iterative method is used to solve the nonlinear equations pertaining displacement terms. This nonlinear behaviour is evaluated for two important types of structural tailoring techniques available for thin-walled composite beams namely Circumferentially Asymmetric Stiffness (CAS) and Circumferentially Uniform Stiffness (CUS). It is found that CAS layup experiences significantly severe nonlinear effects compared to CUS due to the presence of 3rd degree nonlinear coupling terms. The variation of nonlinear frequency ratios over different ply angles showing the influence of nonlinearity on fibres orientation is presented for the first time for the two ply lay ups. The influence of degree of nonlinearity on the accuracy of the nonlinear frequencies is evaluated and presented. Moreover, the impact of nonlinearity on the pre-twisted beam is presented for different pre-twist angles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au/Ce 2 S 3 @CeO 2 /CuS nanocatalysts were prepared for propargylamine synthesis. • Ce 2 S 3 was converted by CeO 2 in Na 2 S due to the different solubility product constant. • Contents of active sites Cu+ and Ce3+ were highly improved in Au/Ce 2 S 3 @CeO 2 /CuS. • A high product conversion rate of 222.5 mmol·g−1·h−1 obtained for Au/Ce 2 S 3 @CeO 2 /CuS. • Au/Ce 2 S 3 @CeO 2 /CuS also showed excellent recyclability, with 80 % retention after 5 cycles. A newly developed nanocomposite catalyst, Au/Ce 2 S 3 @CeO 2 /CuS, has been engineered for effective propargylamine synthesis through the A3 coupling reaction. The catalyst's synthesis involved the targeted addition of 15 wt% CeO 2 to the CuS sulfur precursor, leading to the formation of a Ce 2 S 3 layer due to its lower solubility product constant (K sp). This layer, along with 0.5 wt% Au nanoparticles, significantly increased the Ce3+ concentration (16.9 % to 33 %–52 %), which can accelerate the Cu+/Cu2+ valence state changes, thereby promoting the activation of the alkynyl hydrogen to enhance propargylamine formation. After 2 h reaction, the Au/Ce 2 S 3 @CeO 2 /CuS catalyst achieved over 99 % conversion, nearly 55 % more than pure CuS (45.5 %). The Au/Ce 2 S 3 @CeO 2 /CuS nanocomposite also showed excellent recyclability (80 % retention after 5 cycles) and a high conversion rate of 222.5 mmol·g−1·h−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed dendritic CuS nanostructures by layer-by-layer assembly of amino acid. • Exhibited good photothermal heating efficacy under NIR light (980 nm) irradiation. • NIR irradiation effectively enhanced photothermal toxicity towards cancer cells. • Enhanced cytotoxicity of anticancer drug loaded dendritic system under NIR light. • Potential platform for photoacoustic image guided chemo-photothermal therapy. Herein, we report a unique method for design and development of carboxyl enriched dendritic CuS nanostructures (CuS NSs) for photoacoustic image guided chemo-photothermal therapy. The dendritic network was grown on the surface of CuS nanoparticles via layer-by-layer assembly of amino acid. XRD and TEM studies established the formation of crystalline well-spherical nanosized hexagonal covellite (CuS) phase. The successful growth of dendritic structure was apparent from the rise in surface charge, hydrodynamic diameter and characteristic vibrational band intensity of peptide bonds. The developed different generations of dendritic CuS NSs (D0-CuS NSs, D1-CuS NSs, D2-CuS NSs and D3-CuS NSs) displayed wide-ranging absorption band in near infrared (NIR) zone and exhibited good photothermal heating efficacy upon irradiation of 980 nm laser light. From in - vitro cellular studies, it has been found that the NIR irradiation effectively enhanced the photothermal toxicity of D3-CuS NSs towards cancer cells. Moreover, these negatively charged water-dispersible D3-CuS NSs were conjugated with positively charged anticancer drug, doxorubicin hydrochloride (DOX) through electrostatic interaction. The DOX loaded D3-CuS NSs (DOX@D3-CuS NSs) revealed pH dependent drug release behaviour and their considerable uptake in breast cancer cells (MCF-7). Further, DOX@D3-CuS NSs exhibited a much higher toxicity towards cancer cells upon NIR light over individual counterparts suggesting their strong ability for chemo-photothermal therapy. Moreover, these biocompatible CuS NSs have shown excellent concentration dependent photoacoustic properties at pulse laser excitation (850 nm) and thus, they can be found potential application in chemo-photothermal therapy. [ABSTRACT FROM AUTHOR]

Li ion batteries (LIBs) have emerged as the promising energy storage device in the electronic industry. The performance of LIBs is mostly influenced by the type of electrode material. Thus, proper selection and development of the electrode material is of paramount interest. In this work, copper sulfide/graphene oxide (CuS/GO) composite electrode material is fabricated using a simple, cost-efficient, and rapid microwave irradiation technique. A unique architecture is obtained in which the CuS microspheres are encapsulated by the GO nanosheets. Combined with a binder-free buckypaper approach, the fabricated CuS/GO composite anode delivers excellent electrochemical performance in terms of high specific capacity, enhanced rate capability and high cyclic stability than its pristine form (CuS). The enhanced performance is attributed to the synergistic effect of CuS and GO. The obtained results certainly reflect the promising future of the CuS/GO composite anode in LIB applications.

Hg(II) ions in wastewater are highly toxic to the environment and human health, yet many materials to remove the ions exhibit lower adsorption efficiency, and few studies report the reuse of Hg(II)-loaded waste materials. Here, a cheap and efficient adsorbent was prepared for the removal of Hg(II) based on corn bracts (CB) loading copper sulfide (CuS), and the Hg(II)-adsorbed material was reused as a photocatalyst. By changing the adsorption variables such as pH, adsorbent dosage, Hg(II) concentration, contact time and coexisting ions, the optimum adsorption conditions were obtained. The study indicated the adsorption capacity and removal rate of CB/CuS reached 249.58 mg/g and 99.83% at pH 6 with 20 mg CB/CuS, 50 mL Hg(II) concentration (100 mg/L) and 60 min, and coexisting ions did not affect the uptake of Hg(II). The adsorption behavior of CB/CuS toward Hg(II) followed pseudo-second-order and Langmuir models, with the theoretical maximum adsorption capacity of 316.46 mg/g. Finally, we explored an alternative strategy to dispose of spent adsorbents by converting the CB/CuS/HgS into a photocatalyst for the degradation of rhodamine B, with a removal rate of 98%. Overall, this work not only develops a promising material for the treatment of Hg(II)-containing wastewater, but opens up a new approach for the use of the waste adsorbent. HIGHLIGHTS Corn bracts as a carrier of CuS was designed for rapid uptake of Hg(II).; The removal rate of the adsorbent could reach 99.83% in only 60 min.; The theoretical maximum could reach 316.46 mg/g.; Coexisting ions had no significant effect on selective Hg(II) ion removal.; The spent adsorbent was used for photodegradation reaction.;

The application of metal-organic frameworks (MOFs) in the field of oil-water separation is developing rapidly, but the challenges of poor water stability, poor scalability and durability still limit its practical application. In this study, two environmentally friendly and non-toxic superhydrophobic (Cu, Zn)S/(Cu-, Zn-)MOFs@stearic acid (CuS/Cu-MOFs@SA and ZnS/Zn-MOFs@SA) coatings were successfully prepared by hydrothermal method combined with dip coating method, with a water contact angle (WCA) of >165°. Through the synergistic effect with stearic acid (SA), the (Cu-, Zn-)MOFs coating composited with CuS and ZnS exhibits excellent durability in extreme environments. This synergistic effect significantly improves the mechanical stability and durability of the coating, allowing it to maintain a WCA of >155° after friction, kneading, tape stripping and ultrasonic treatment. However, CuS/Cu-MOFs@SA coating is significantly superior to ZnS/Zn-MOFs@SA coating in terms of chemical stability (acid-base-salt environment) and self-cleaning ability due to the different ligands used in the preparation process and the formation of particle structure. Significantly improved its durability and reliability in oil-water separation. The separation efficiency of the coating is as high as 98.7 %, and it remains above 97.8 % after 12 times of repeated use. This study provides a new strategy and important reference for the development of superhydrophobic MOFs coatings and oil-water separation materials with high stability, wear resistance and corrosion resistance. [Display omitted] • Developed superhydrophobic CuS/Cu-MOFs@SA and ZnS/Zn-MOFs@SA coatings. • Coatings offer exceptional mechanical stability and longevity. • High efficiency in separating oil from water. • Enhanced chemical and mechanical durability through CuS, ZnS, and SA integration. • Improved cotton fabric superhydrophobicity, minimizing surface adhesion. [ABSTRACT FROM AUTHOR]

[Display omitted] • The rough surface and hollow-cage structure make CuS HNCs have plenty of hot spots. • CuS HNCs display strong LSPR and high photothermal conversion efficiency of 42.39%. • An ultra-sensitive colorimetric/photothermal LFIA was constructed based on CuS HNCs. • LODs of the dual-modal LFIA for AOZ are 0.099 ng mL−1 (CM) and 0.075 ng mL−1 (PT). Signal tracers play a key role in the lateral flow immunoassay (LFIA) for improving sensitivity and signal output capability. Photothermal signal has sparked significant excitement in designing high-performance LFIAs. Herein, CuS hollow nanocages (CuS HNCs) were synthesized for building a dual signal LFIA. CuS HNCs show excellent photothermal conversion efficiency due to their unique morphology and superior localized surface plasmon resonance (LSPR) effect. Meanwhile, the hollow-cage structure endows CuS HNCs with high light absorption and suitable colorimetric property. Furazolidone (FZD) metabolite was used as a model target in the developed LFIA to demonstrate its superior comprehensive performances brought by CuS HNCs. The limit of detection is as low as 0.099 ng mL−1 (colorimetric mode) and 0.075ng mL−1 (photothermal mode), respectively. Furthermore, standard recovery test in honey and shrimp samples was performed and the recovery rates ranged from 86.33 % to 116.71 %. This study not only introduces a new type of nanolabel characterized by an abundance of high-energy hot carriers and pronounced thermal effects, enabling the development of exceptionally sensitive immunosensor platforms but also extends applications of hollow plasmonic photothermal material in the point-of-care (POC) diagnostic field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Providing a strategy to synthesize CuS-NPC. • CuS-NPC improves specific capacity and electronic conductivity. In this work, an electrode composite (CuS-NPC) for supercapacitors was synthesized by loading hexagonal nano-sheeted copper sulfide onto porous carbon through a solvothermal reaction using thiourea and copper acetate as the sulfur and copper sources, respectively. The synergistic effect of nanoscale copper sulfide sheet and hierarchical pore structure of porous carbon with high surface area achieves excellent capacitive performance in electrochemical reactions. CuS-NPC exhibited a large specific capacitance of 1298.7F g−1 at current density of 0.5 A/g and 766.3F g−1 at current density of 10 A/g, revealing that the electrode composite of copper sulfide and porous carbon have a great prospect as a supercapacitor electrode material. [ABSTRACT FROM AUTHOR]

Interfacial solar desalination generation (ISDG) presents a promising solution for obtaining freshwater from seawater. However, developing solar evaporators with robust salt resistance using simple methods to ensure consistent desalination performance remains a major challenge. In this study, we engineered a solar evaporator (CuS-PDA-PVAF) by modifying polyvinyl alcohol foam (PVAF) with polydopamine (PDA) and CuS using a straightforward solution immersion method. The incorporation of PDA and CuS enhances the sunlight absorption capability of PVAF to approximately 98 %, resulting in an evaporation rate of 1.44 kg m–2 h–1 under 1-solar intensity. The CuS-PDA-PVAF solar evaporator leverages the macroporous structure and excellent hydrophilicity, enabling it to withstand 15 wt% saltwater while maintaining a steady evaporation rate of about 1.17 kg m–2 h–1. Outdoor tests confirm that a 1 m2 CuS-PDA-PVAF can generate approximately 5.6 kg of freshwater daily. This solar evaporator, designed simply and resistant to salt, possesses substantial potential for alleviating freshwater scarcity. • CuS-PDA-PVAF was designed with a simple solution immersion method. • CuS improves the sunlight absorption of PDA-PVAF to 98 %. • CuS-PDA-PVAF can steadily resist 15 wt% saltwater. • 1 m2 CuS-PDA-PVAF can produce about 5.6 kg of freshwater per day. [ABSTRACT FROM AUTHOR]

Chronic stress caused by prolonged emotional pressure can lead to various physiological issues, including reproductive dysfunction. Although reproductive problems can also induce chronic stress, the impact of chronic stress-induced reproductive dysfunction remains contentious. This study investigates the effects of chronic unpredictable stress (CUS) on reproductive neuropeptides, sperm quality, and testicular morphology. Sixteen twelve-week-old Sprague Dawley rats were divided into two groups: a non-stress control group and a CUS-induced group. The CUS regimen involved various stressors over 28 days, with both groups undergoing behavioural assessments through sucrose-preference and forced-swim tests. Hypothalamic gene expression levels of CRH, PNX, GPR173, kisspeptin, GnRH, GnIH , and spexin neuropeptides were measured via qPCR, while plasma cortisol, luteinizing hormone (LH), and testosterone concentrations were quantified using ELISA. Seminal fluid and testis samples were collected for sperm analysis and histopathological evaluation, respectively. Results showed altered behaviours in CUS-induced rats, reflecting stress impacts. Hypothalamic corticotropin-releasing hormone (CRH) expression and plasma cortisol levels were significantly higher in CUS-induced rats compared to controls (p < 0.05). Conversely, phoenixin (PNX) expression decreased in the CUS group (p < 0.05), while kisspeptin, spexin , and gonadotropin-inhibitory hormone (GnIH) levels showed no significant differences between groups. Despite a significant increase in GnRH expression (p < 0.05), plasma LH and testosterone concentrations were significantly lower (p < 0.05) in CUS-induced rats. Histopathological analysis revealed abnormal testis morphology in CUS-induced rats, including disrupted architecture, visible interstitial spaces between seminiferous tubules, and absence of spermatogenesis. In conclusion, CUS affects reproductive function by modulating PNX and GnRH expression, influencing cortisol levels, and subsequently reducing plasma LH and testosterone concentrations. This study highlights the complex interplay between chronic stress and reproductive health, emphasizing the significant impact of stress on reproductive functions. • Chronic stress has recently associated with decreasing of reproductive health quality among males. • Chronic stress significantly reduced reproductive neuropeptides gene expression, phoenixin levels and reproductive hormones. • CUS influences reproductive function by modulating phoenixin and GnRH expression. • Testis and sperm morphology are severely affected by the CUS induced. [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]

The abundant aromatic ring structure and a large number of oxygen-containing functional groups in the lignin offer the possibility of achieving excellent photothermal conversion ability and modulating the synthesis of metal nanoparticles. Herein, three kinds of the lignin with different functional group content were employed to investigate the potential influence on the particle size and the solution stability of the CuS through two reaction pathways. The result of various characterizations indicated that the higher the oxygen-containing functional group content (4.83 mmol/g) of lignin, the smaller the size of CuS nanoparticles (∼80 nm) in solution. And the smaller and homogeneously dispersed CuS offered a higher surface temperature for the solar-driven heat-generating materials. The regulation mechanism was also proposed based on the result of the molecular dynamics simulation and DFT calculation. Subsequently, the photothermal film (Route2 DTAL-PVA-30) and solar-driven aerogel evaporator (Route2 DTAL-AG3) were successfully prepared using the lignin-guided stabilization solution of CuS nanoparticles. The photothermal conversion efficiency of 49.43 % and the equilibrium voltage of 266 mV can be achieved by the Route2 DTAL-PVA-30 under 1 sun using a thermoelectric generator. The Route2 DTAL-AG3 exhibited promising salt-rejecting property and outstanding acid and alkali resistance performance, reaching an evaporation rate of up to 1.93 kg/(m2 h) in the 3.5 wt% seawater under 1sun. This work may provide a novel strategy to realize the regulatory role of lignin in the metal synthesis and achieve the high value-added applications of the lignin. [Display omitted] • The influence of the functional group in lignin on the synthesis process of CuS was investigated. • The regulation mechanism of the lignin on the synthesis process of the CuS was clarified. • The photothermal conversion efficiency of Route2 DTAL-PVA-30 can reach as high as 49.43 %. • The equilibrium voltage of 381 mV can be achieved by the Route2 DTAL-PVA-30 under 3 sun. • The Route2 DTAL-AG3 can reach an evaporation rate as high as 4.83 kg/(m2 h) under 3 sun. [ABSTRACT FROM AUTHOR]

All-solid-state batteries (ASSBs) by utilizing sulfide electrolytes (SEs) have recently attracted much attention because of their advantages such as high ionic conductivity and low processing temperature of SEs. To enhance the electrochemical properties of ASSBs such as areal capacity and cycle performance, it is highly desired to obtain an intimate contact between active materials and SEs in the cathode and decrease the content of non-active materials including electronically conductive carbon and SEs. In this work, a carbon-free composite cathode with CuS as the active material and lithium argyrodite Li 5.5 PS 4.5 Cl 1.5 (LPSCl) as the SE was prepared by ball milling. Due to the tight contact between LPSCl and CuS caused by ball milling, high theoretical specific capacity, and relatively large electronic conductivity of CuS, the ASSB with a composite cathode containing a CuS loading of 10.2 mg cm−2 delivered a large initial discharge capacity of 434.3 mAh g–1 electrode based on the cathode mass and a high areal capacity of 5.5 mAh cm−2 at room temperature. At a higher CuS loading of 20.4 mg cm−2, an ultrahigh areal capacity of 12.7 mAh cm−2 and a calculated specific energy of 955 Wh kg–1 electrode based on the cathode were obtained at 60 °C. Our work demonstrates that the carbon-free, CuS-based composite cathode is a highly promising cathode for high-energy-density ASSBs. [Display omitted] • A carbon-free CuS-based cathode for all-solid-state batteries is reported. • An intimate contact between CuS and sulfide electrolyte is achieved. • An ultrahigh areal capacity of 12.7 mAh cm−2 is obtained for the cathode. • The energy density based on the total mass of the cathode is 955 Wh kg–1. [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]

DOX@H-Cu 9 S 8 /PEG with photothermal effect, Fenton-like catalytic performance, and drug-loading capacity serve as an efficient nanoplatform for photothermally-augmented chemodynamic-chemo therapy. [Display omitted] • Construction of hollow Cu 9 S 8 through Kirkendall effect and with high photothermal effect. • Enhanced Fenton reaction by NIR-driven photothermal effect. • Controlled DOX-releasing due to pH/photothermal effect. • High therapeutic efficacy from photothermally-augmented chemodynamic-chemo therapy. Multimodal therapy has attracted increasing interests in tumor treatment due to its high anti-cancer efficacy, and the key is to develop multifunctional nanoagents. The classic multifunctional nanoagents are made up of expensive and complex components, leading to limited practical applications. To solve these problems, we have developed the polyethylene glycol (PEG) coated hollow Cu 9 S 8 nanoparticles (H-Cu 9 S 8 /PEG NPs), whose H-Cu 9 S 8 component exhibits the photothermal effect for near-infrared (NIR) photothermal therapy (PTT), the Fenton-like catalytic activity for chemodynamic therapy (CDT), and the drug-loading capacity for chemotherapy. The H-Cu 9 S 8 /PEG NPs with a diameter of ∼ 100 nm have been synthesized by sulfurizing cuprous oxide (Cu 2 O) nanoparticles through "Kirkendall effect", and they exhibit high photothermal conversion efficiency of 40.9%. Meanwhile, the H-Cu 9 S 8 /PEG NPs are capable of a Fenton-like reaction, which can be augmented by 2 times under the NIR irradiation. The hollow structure gives the H-Cu 9 S 8 /PEG high doxorubicin (DOX) loading capacity (21.1%), and then the DOX release can be further improved by pH and photothermal effect. When the DOX@H-Cu 9 S 8 /PEG dispersions are injected into the tumor-bearing mice, the tumor growth can be efficiently inhibited due to the synergistic effect of photothermally-augmented CDT-chemo therapy. Therefore, the DOX@H-Cu 9 S 8 /PEG can serve as a multifunctional nanoplatform for photothermally-augmented CDT-chemo treatment of malignant tumors. [ABSTRACT FROM AUTHOR]

[Display omitted] Designing photothermal transducing agents (PTAs) with enhanced photothermal conversion efficiency (PCE) holds essential importance for photothermal tumor eradication applications. Currently, it is an effective way to improve the photothermal efficiency by designing the energy level transition leading to the enhancement of UV absorption. To address the challenge, we develop novel Prussian blue@polyacrylic acid/copper sulfide Janus nanoparticles (PB@PAA/CuS JNPs) via selective coating of PAA nano-hemisphere on one of the surfaces of PB NPs followed by the further formation of CuS on the PAA template. The experiments show that the energy level transition occurs between Janus structure. Besides, it offers enhanced absorption over NIR-I and NIR-II dual windows. The muscle tissue penetration studies suggest that the PB@PAA/CuS JNPs have deeper tissue penetration in the 1064 nm laser irradiation group, indicating their potential for treating deep-tissue-seated tumors. In a word, the unique PB@PAA/CuS JNPs show an enhanced tumor inhibitory effect over the NIR-I and NIR-II dual windows, which will open up new opportunities for improving PTT efficiency by the rational nanostructural design of PTAs. [ABSTRACT FROM AUTHOR]

The functional properties of (1-x)CuCo2O4/(x)CuS nanocomposite as an improved supercapacitor electrode have been investigated. X-ray diffraction with Rietveld analysis, HRTEM, FESEM, and FTIR techniques were employed for the full structural characterization of the nanocomposites. The particle size and morphology, the phase composition and percentage, the lattice parameters, the cation distribution and the crystallite size were accurately determined for the prepared samples. The variation of the bandgap of the phases developed with the alloying parameter (x) was studied utilizing the UV diffuse spectrum. All samples exhibited a blue shift except the sample with x = 0.25, it revealed a redshift. The photoluminescence intensity and the color emitted were affected by CuCo2O4 and CuS alloying. The preliminary test of cyclic voltammetry (CV) proved that alloying of CuS nanoparticles with CuCo2O4 enhanced the electrochemical activities, and optimum performance achieved with allying ratio x = 0.25.

Flexible energy storage devices are an essential step towards the production of wearable and flexible electronic products. However, the design of flexible electrodes with excellent electrochemical performance still faces enormous challenges. This work reports a fabrication method for flexible electrodes. Specifically, the formation of MC‐CuS‐PGr/PPy nanocomposite films was driven by different interactions (including hydrogen bonds and π–π conjugated bonds). Nanocellulose@carbon nanotube (MC) acted as a flexible substrate and was encapsulated with polypyrrole (PPy), a hydrogen bond active site carrier. MC and PPy were interconnected through hydrogen bonds, and pencil graphite (PGr) was a secondary conductive network that served as a separating layer between CuS and PPy. Driven by the interaction, the nanocomposite film was a stable combination. The strong macromolecular interactions among MC, PPy, and PGr enhance conductivity and cycle life of this nanocomposite films. The water‐based hybrid cell was assembled based on an MC‐CuS‐PGr/PPy nanocomposite film, which exhibited high cyclability (capacity retention of 94.3% after 2000 cycles at 1 Ag−1) and provided an energy density of Wh kg−1 (at a power density of 549.8 W kg−1). This research provides a new idea for preparing new flexible electrodes. [ABSTRACT FROM AUTHOR]

Nano-ZnMn2O4 sample was coupled with nano-CuS using co-precipitation and thermolysis methods. All X-ray patterns for different values of alloying parameter (x) in (1–x) ZnMn2O4/xCuS (x = 0, 0.1, 0.15, 0.2) system, disclosed only single tetragonal ZnMn2O4 (ZMO) phase. Rietveld refinement examined the distortion in tetrahedral and octahedral sites of ZMO upon coupled with CuS. The cation distribution between different sites was also investigated using Rietveld analysis method. The cell parameters were affected by the composition of the sample and dragging effect. The effect of solid solution between ZMO and CuS, on tetrahedral and octahedra bands of ZMO phase was studied. X-ray photoelectron spectroscopy spectra were measured to confirm the incorporation of Cu and S ions into the ZMO lattice and to determine the oxidation states of different ions. The optical band gap energies for (1–x)ZnMn2O4/xCuS samples are 2.49, 2.57, 2.61, and 2.55 eV; x = 0, 0.1, 0.15, and 0.2, respectively. The effect of the insertion of Cu and S ions in the ZMO lattice on the different optical parameters and emitted colors was explored using UV diffused reflectance and photoluminescence spectrophotometer techniques. Highlights: Cu and S ions dissolved into the ZnMn2O4 (ZMO) lattice to form nano-(1–x)ZnMn2O4/xCuS solid solution. XPS confirmed the existence of sulfur in ZMO matrix and the presence of Mn in two oxidation states (2, 3). The optical band gap of the solid solution samples was increased irregularly as the number of Cu and S ions increased in ZMO matrix. (1–x)ZnMn2O4/xCuS samples can be used in capacitance and shorter response time's device. The reduction in PL intensity in the solid solution sample with x = 0.2 nominated their applications as photo-catalysts. [ABSTRACT FROM AUTHOR]

Incorporation of metal nanoparticles (NPs) into various layers of organic solar cells (OSCs) has become a popular means of enhancing device performances through increased light absorption by way of plasmon resonance effects. A number of NPs properties and device fabrication parameters should be considered when designing NPs-embedded OSCs for achieving optimum photovoltaic performance. Understanding the impact and mechanisms of photo-absorption with NPs in the solar cells becomes important, making numerical simulations for such investigations critical. Adopting the effective medium model in a numerical simulation; we have investigated charge transport and recombination dynamics of copper sulfide nanoparticles (CuS NPs)-doped hole transport layer (HTL) in OSC. The P3HT:PCBM blend bulk heterojunction (BHJ) solar absorber is used in modeling the devices. The CuS NPs-doping of the hole transport layer (HTL) was realized by introducing a thin modified hole selective layer (MHSL) between the HTL and the absorber. Non-ideal factors such as limited mobility, traps states, recombination dynamics and adjusted exciton generation profiles were considered to describe the solar cells. Enhanced conductivity, variations in the Fermi level offset at the interface and thickness of the MHSL were also taken into account to analyze device performances. The results were compared with experimentally measured device parameters, which are found to be in good agreement. These will greatly assist in understanding the physical processes in nanoparticles-doped OSCs. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Although transition metal sulfides have presented prospect in electrochemical sensing, their electrocatalytic performance still cannot meet the demands for practical applications due to the difficulties in mass transport and electron transfer. In this work, double-shelled CuS nanocages (2-CuS NCs) were prepared for enzyme-free ascorbic (AA) sensor through a Cu2O- templated method. The unique double-shelled hollow structure displayed large specific surface areas, ordered diffusion channels, increased volume occupying rate, and accelerated electron transfer rate, resulting in enhanced electrochemical dynamic. As a sensing electrode for AA, 2-CuS NCs modified glassy carbon electrode (2-CuS NCs/GCE) exhibited eminent electrocatalytic activity in terms of satisfying sensitivity (523.7 μA mM−1 cm−2), short response time (0.31 s), and low limit of detection (LOD, 0.15 μM). 2-CuS NCs look promising for analytical sensing of AA in electrochemical sensors thanks to its prominent electrocatalytic kinetics issued from double-shelled hollow porous structure.

Nanoparticles of copper sulfide have been prepared by simple reaction between using copper nitrate with different concentrations ratio 0.1, 0.3, and 0.5 mM, thiourea by a simple chemical route. The prepared Nano powders have been deposited onto glass substrates by casting method at 60°C. The structure of the product Nano- films has been studied by x-ray diffraction, where the patterns showed that all the samples have a hexagonal structure of covellite copper sulfide with the average crystalline sizes 14.07- 16.51 nm. The morphology has been examined by atomic force microscopy, and field emission scan electron microscopy. The AFM images showed particles with almost spherical and rod shapes with average diameter sizes of 49.11- 90.64 nm. From the UV-Vis absorption studies, it has been noted that the increased absorption edge for all thin films leads to decreases in the energy gap of 3.5 to 3.0 eV for 1mM and 5mM respectively.

Ouabain (OUA) is a cardiotonic steroid that modulates Na+, K+ -ATPase activity. OUA has been identified as an endogenous substance that is present in human plasma, and it has been shown to be associated with the response to acute stress in both animals and humans. Chronic stress is a major aggravating factor in psychiatric disorders, including depression and anxiety. The present work investigates the effects of the intermittent administration of OUA (1.8 μg/kg) during the chronic unpredictable stress (CUS) protocol in a rat’s central nervous system (CNS). The results suggest that the intermittent OUA treatment reversed CUS-induced HPA axis hyperactivity through a reduction in (i) glucocorticoids levels, (ii) CRH-CRHR1 expression, and by decreasing neuroinflammation with a reduction in iNOS activity, without interfering with the expression of antioxidant enzymes. These changes in both the hypothalamus and hippocampus may reflect in the rapid extinction of aversive memory. The present data demonstrate the ability of OUA to modulate the HPA axis, as well as to revert CUS-induced long-term spatial memory deficits.

Herein, well-defined hollow CuS microspheres assembled from nanosheets were successfully synthesized through a facile solvothermal method. Hollow CuS microspheres have an average diameter of 1.5 μm; moreover, the primary CuS nanosheets have an ultrathin thickness of about 10 nm and are bound by {0001} polar facets. When used as anodes for lithium-ion batteries (LIBs), hollow CuS microspheres exhibit excellent electrochemical properties, including a large discharge capacity (610.1 mAh g−1 at 0.5 C), an excellent rate capability (207.6 and 143.4 mAh g−1 at 1 and 5 C), and a superior cyclic stability (196.3 mAh g−1 at 1 C after 500 cycles). When used as photocatalysts for Rhodamine B (RhB), hollow CuS microspheres can degrade more than 99% of the initial RhB within 21 min. These excellent Li-ion storage properties and photocatalytical performances are attributed to their unique hierarchical hollow structure.

In this paper, a novel S-scheme CuS/Bi5O7I heterojunction was successfully constructed using a two-step approach comprising the alkaline hydrothermal method and the adsorption–deposition method, and it consisted of Bi5O7I microrods with CuS particles covering the surface. The photocatalytic antibacterial effects on Escherichia coli (E. coli) were systematically examined with visible light exposure. The results suggested that the 3%-CuS/Bi5O7I composite showed the optimal antibacterial activity, completely inactivating E. coli (5 × 108 cfu/mL) in 180 min of irradiation. Moreover, the bacterial inactivation process was scientifically described. •O2− and h+ were the major active species for the inactivation of the bacteria. In the early stages, SOD and CAT initiated the protection system to avoid the oxidative destruction of the active species. Unfortunately, the antioxidant protection system was overwhelmed thereafter, which led to the destruction of the cell membrane, as evidenced by the microstructure changes in E. coli cells. Subsequently, the leakage of intracellular components including K+, proteins, and DNA resulted in the unavoidable death of E. coli. Due to the construction of the S-scheme heterojunction, the CuS/Bi5O7I composite displayed the boosted visible light harvesting, the high-efficiency separation of photogenerated electrons and holes, and a great redox capacity, contributing to an outstanding photocatalytic disinfection performance. This work offers a new opportunity for S-scheme Bi5O7I-based heterojunctions with potential application in water disinfection.

Diabetic wounds are prone to recurrent infections, often leading to delayed healing. To address this challenge, we developed a chitin-copper sulfide (CuS@CH) composite sponge, which combines bacterial trapping with near-infrared (NIR) activated phototherapy for treating infected diabetic wounds. CuS nanoparticles were synthesized and incorporated in situ within the sponge using a chitin assisted biomineralization strategy. The positively charged chitin surface effectively adhered bacteria, while NIR irradiation of CuS generated reactive oxygen species (ROS) heat and Cu 2+ to rapidly damage the trapped bacteria. This synergistic effect resulted in an exceptional antibacterial performance against E. coli (∼99.9%) and S. aureus (∼99.3%). The bactericidal mechanism involved NIR-induced glutathione oxidation, membrane lipid peroxidation, and increased membrane permeability. In diabetic mouse models, the CuS@CH sponge accelerated the wound healing of S. aureus infected wounds by facilitating collagen deposition and reducing inflammation. Furthermore, the sponge demonstrated good biocompatibility. This dual-functional platform integrating bacterial capture and NIR-triggered phototherapy shows promise as an antibacterial wound dressing to promote healing of infected diabetic wound.

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]

Although supercapacitors have attracted more and more attention owing to their fast charging speed and high power density, their wide applications have still been limited by their low energy density. In this study, a new CuS-nanoparticle-decorated Ti3C2T x electrode material is fabricated via a facile in situ synthesis strategy at room temperature. CuS nanoparticles, generated from the in situ reaction of Cu (NO3)2·3H2O with Na2S·9H2O, are anchored between the Ti3C2T x interlayers through electrostatic interaction. This type of structural construction is found capable of not only reducing the surface oxidation of Ti3C2T x , but also preventing the accumulation of CuS nanoparticles by the template effect of Ti3C2T x nanoplates. As a result, the CuS/Ti3C2T x nanohybrid delivers a maximum specific capacitance of 911 F gâˆ'1 at 1 A gâˆ'1 and a good cycling stability. A symmetric supercapacitor fabricated using the CuS/Ti3C2T x nanohybrid as the electrode material exhibits an energy density of 43.56 W h kgâˆ'1 with a power density of 475 W kgâˆ'1. Consequently, this work provides a new perspective of microstructural design for the preparation of electrode materials with superhigh specific capacitance through an easy and low-cost in situ -reaction method at room temperature. [ABSTRACT FROM AUTHOR]

Semiconductor-based photocatalysis represents a promising technology for removing antibiotic given its cost effectiveness and environmental compatibility. However, finding suitable photocatalysts and semiconductors for practical applications can be challenging. This work aims to investigate the photocatalytic performance of as-synthesized photocatalysts under broad-spectrum from visible (Vis) to near-infrared (NIR) sunlight. In this work, a step-scheme (S-scheme) heterojunction photocatalyst, i.e., CuS/S–C 3 N 4 , was prepared, employing a single-step hydrothermal route. The synthesized photocatalyst showed excellent crystallinity and high purity content. The CuS loading provided a better NIR light response-ability and improved photocatalytic activity for CuS/S–C 3 N 4. The 2 wt% CuS/S–C 3 N 4 produced the highest tetracycline (TC) photodegradation rate, up to about 95% efficiency under Vis + NIR light irradiation. The result also showed that the 2 wt% CuS/S–C 3 N 4 sample had a first-order kinetic constant (k) that was 6.2-fold higher than the pure S–C 3 N 4 sample under Vis + NIR light irradiation. However, too much CuS content led to the presence of inactive sites on S–C 3 N 4 , which hampered the light absorption ability, thus leading to inadequate photocatalytic activity. In addition, the 2 wt% CuS/S–C 3 N 4 sample also showed high photocatalytic stability and insignificant change of the composite structure before and after the experiments. In short, we can enhance the CuS/S–C 3 N 4 photocatalytic activity by increasing the light response range and the separation efficiency of light-induced electrons and holes. Consequently, we have developed a novel strategy and experimental basis for S-scheme heterojunction to be fully utilized under broad-spectrum sunlight. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Composite heterostructure photocatalysts can effectively improve photocatalytic performance. For narrow‐bandgap semiconductors, such as Bi2S3, constructing heterostructures with other semiconductors can obviously promote the separation of photogenerated electron−hole pairs and improve their photocatalytic performance. However, some basic and important parts of this technology still require further clarification. Herein, the interface properties of CuS/Bi2S3 heterostructure was studied using density functional theory calculations. The results show that the electronic structure of the interface model shows some different characteristics compared with the bulk and surface models due to the different bonding modes and chemical environments at the interface. At the interface of the CuS/Bi2S3 heterostructure, the band edge of CuS is bent downward relative to Bi2S3 to form a type II heterostructure. In addition, in the equilibrium state, the direction of the built‐in electric field of the heterostructure is from Bi2S3 to CuS. Therefore, the photogenerated electron−hole pairs can be separated by the CuS/Bi2S3 interface, which is extremely advantageous for the improvement of photocatalytic performance. The formation of the CuS/Bi2S3 heterostructure not only broadens the light absorption of CuS but also suppresses the recombination of photogenerated electron−hole pairs of the narrow‐bandgap semiconductor Bi2S3. [ABSTRACT FROM AUTHOR]

[Display omitted] • The In 2 O 3 +ZrO 2 physical mixture (PM) is much more active than its components. • PM generates isobutene at high selectivity while its components almost do not. • DRX and XPS showed that ZrO 2 promotes distortions in the In 2 O 3 lattice. • The distortions turn easier the generation of O vacancies during the reaction. • PM catalytic performance is associated with the facility of vacancies generation. A physical mixture comprising In 2 O 3 and ZrO 2 and its components were employed as catalysts in the generation of isobutene from ethanol. These solids were characterized by means of several techniques such as EPR, HRTEM, XPS, XRD, N 2 physical adsorption, isopropanol-TPD, CO 2 -TPD, ethanol-TPD and pyridine adsorption. The addition of 7% of In 2 O 3 to ZrO 2 employing the physical mixture procedure generates a catalyst which shows physicochemical and catalytic properties which are not a linear combination of its components properties. This catalyst is not only much more active compared with In 2 O 3 and ZrO 2 , but it also generates isobutene at high selectivity. The interaction between In 2 O 3 and ZrO 2 changes the quantity and strength of the acidic and basic sites. However, these modifications do not correlate with the catalytic behavior. The HRTEM data suggest that the epitaxy alignment occurs between these two oxides which might cause stresses in the In 2 O 3 lattice. The XRD and XPS analysis have identified distortions in the In 2 O 3 lattice provoked by ZrO 2 , which facilitate the generation of O vacancies and consequently increases the concentration of these species during the reaction. This phenomenon promotes the acetone and acetaldehyde syntheses which are very relevant intermediate of this cascade reaction. Thus, it can be suggested that the catalytic behavior of the modified physical mixture is associated with the In 2 O 3 lattice distortions promoted by ZrO 2. [ABSTRACT FROM AUTHOR]

In the emerging field of electrochemical energy storage devices (EESDs), lithium (Li) ion-based EESDs are currently dominant. However, due to the high cost and lack of Li resources, researchers and industries look forward to replace Li with low-cost, safe, and highly abundant elements. Nowadays, immense research work on sodium (Na+), magnesium (Mg2+), and potassium (K+) ion–based EESDs are going on to replace Li-based EESDs. For any EESDs, the selection of a good electrolyte is a crucial task. The interaction of any ions with the electrode materials depends on the ionic radii, hydrated sphere size, conductivity, viscosity, and other parameters of selected electrolyte ions. In this manuscript, we explored the electrochemical behaviour of cationic species of various electrolytes (such as Na2SO4, MgSO4, K2SO4, and Li2SO4) with pseudocapacitive copper sulphide (CuS) electrodes. CuS is synthesized by a simple wet chemical route and characterized by various analytical techniques. Cyclic voltammetry and charge–discharge studies reveal that cations of each electrolyte are uniformly participating in the reduction and oxidation process. The rising trade of capacitance is observed with cations Li+ < K+ < Mg2+ < Na+. Pseuodocapacitive contribution profile of CuS with each electrolyte confirming that the charge storage mechanism of cations is mainly controlled by both diffusion and capacitive process. The electrochemical impedance spectroscopy profile of the examined electrolytes reveals that the Na+ ions show a low charge transfer resistance (2.497 Ω) as compared to others, which conclude that the Na+ ion–based electrolyte is an appropriate choice for the EESDs. [ABSTRACT FROM AUTHOR]

Pilots and crew of domestic flights are exposed to transient periods of mild reductions of partial pressure of inspired oxygen each day, and this might have functional consequence on their performance in the long range. Here, we exposed mice to mild reductions of oxygen exposure (ROE) four times per day for 21 days by lowering oxygen partial pressure to levels corresponding to an altitude of about 2300 m, which is the quote of pressurization of the air cabin. Four groups of mice were studied: unstressed or stressed mice exposed to ROE or normoxic conditions. Mice were exposed to chronic unpredictable stress (CUS) for 28 days, and ROE was delivered in the last 21 days of CUS. In normoxic mice, CUS caused anhedonia in the sucrose preference test, anxiety‐like behaviour in the open field test, learning impairment in the Morris water maze, reduced hippocampal neurogenesis, increased serum corticosterone levels and increased expression of depression‐related genes (Pclo, Mthfr and Grm5) in the hippocampus. All these changes were reversed by ROE, which had little or no effect in unstressed mice. These findings suggest that ROE simulating air cabin conditions of domestic flights may enhance resilience to stress improving mood, anxiety and learning ability. [ABSTRACT FROM AUTHOR]

(1−x) CuCo2O4-xCuS (x = 0, 0.1, 0.25, 0.5) nanocomposite samples were prepared using hydrothermal and thermolysis procedures. The crystal structure and the percentages of phases formed in the nanocomposite samples were studied employing Fullprof software. X-ray photoelectron spectroscopy (XPS) was carried out to identify the different ions present in samples and their oxidation states. The specific capacitance is remarkably enhanced after adding CuS emphasizing the synergistic effect between CuCo2O4 and CuS. The optimum performance of 735 Fg−1 was achieved for 25% CuS. At a higher amount of CuS, the electrochemical activities become less compared with a low CuS amount. The supercapacitor electrode of 0.75CuCo2O4/0.25CuS exhibited high stability with a longer discharging time compared with pristine CuCo2O4 and CuS. Also, it maintained 88.9% of its initial Cs and consequently, this material can work as an excellent supercapacitor electrode. Electrochemical impedance spectroscopy (EIS) analysis was also performed. [ABSTRACT FROM AUTHOR]

There are growing interests in the development of bifunctional semiconducting nanostructures for photocatalysis and real-time monitoring of degradation process on catalysts. Defect engineering is a low-cost approach to manipulating the properties of semiconductors. Herein, we prepared CuS nanoplates by a hydrothermal method at increasing amounts of thioacetamide (CS-1, CS-2, and CS-3) and investigated the influence of sulfur vacancy (Vs) on surface-enhanced Raman spectroscopy (SERS) and photocatalysis performance. SERS intensity of 4-nitrobenzenethiol on CS-3 is 346 and 17 times that of CS-1 and CS-2, respectively, and enhancement factor is 1.34 × 104. Moreover, SERS is successfully applied to monitor the photodegradation of methyl orange. In addition, CS-3 also exhibited higher efficiency of Cr(VI) photoreduction than CS-1 and CS-2, and removal rate is 88%, 96%, and 73% under 2 h UV, 4 h visible, and 4 h near-infrared illumination, respectively. A systematic study including electron paramagnetic resonance spectra, photoelectrochemical measurements, and nitrogen adsorption isotherms were conducted to investigate the underlying mechanism. This work may help to understand the impact of vacancy defect on SERS and photocatalysis, and provide an effective and low-cost approach for the design of multifunctional materials.

At present, the development of lightweight and wideband microwave absorbing materials with stable infrared stealth property and adaptable to complex environments has become the key to multi-modal stealth technology. Herein, hollow CuS microflowers were self-assembled on biomass-derived porous carbon in situ to realize the multifunctions of microwave absorption, flame retardance and thermal stealth. The multicomponent synergistic effect combined with unique microarchitecture triggered the multiple polarization effects, multiple reflection and scattering as well as conduction loss in the PC@CuS composite. As a result, the PC 800 @CuS sample exhibited an optimal RL min of −61.5 dB and an exceptionally wide EAB of 7.8 GHz with the filling ratio of only 10%. In addition, the PC@CuS composite also exhibited superior flame-retardant properties by virtue of its distinctive porous structure. Meanwhile, the uniform distribution of CuS particles played a vital role in enhancing the overall infrared absorption efficiency, thereby obtaining stable and highly-effective infrared stealth performance comparable to commercial products. This work shed light on the development of high-efficiency MAs with multifunctions in a facile and low-cost manner. • The synthesis process was low-cost, facile and green. • The RL min of −61.5 dB and EAB of 7.8 GHz were achieved at a filling ratio of 10%. • A microwave absorber with thermal stealth was fabricated. [ABSTRACT FROM AUTHOR]

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 flowerlike copper sulfide (CuS)/reduced graphene oxide (rGO) composites were prepared successfully by the hydrothermal method. The active anodic material was characterized by Raman spectroscopy, thermogravimetric analyses (TGA), transmission electron microscopy (TEM), and electrochemical techniques. TEM images showed that the flowerlike CuS is well combined with rGO. The electrochemical tests indicate that the presence of rGO improves the electrochemical performance of the CuS, achieving an initial high discharge capacity of 3401 mAh g−1 and initial charge capacity of 1064 mAh g−1, superior to that exhibited for pure CuS (765.2 mAh g−1 and 318.9 mAh g−1). The reason for this is that the addition of rGO increases the surface area and conductivity of the material. The changes enable the composite material more effectively to adapt to the severe volume changes during charging and discharging. [ABSTRACT FROM AUTHOR]

In this work, gallium doped copper sulfide (Ga-doped CuS) nanocrystals were prepared using a solvothermal method. The effects of Ga doping on the crystal structures, chemical composition, morphology, optical properties and thermal performance of copper sulfide (CuS) were investigated. The Ga-doped CuS nanocrystals had a hexagonal structure comparable to that of pure CuS. The Cu+/Cu2+ ratio first decreased and then increased with increasing Ga3+ doping. Both CuS and Ga-doped CuS exhibited nanoplate and nanorod morphologies. The visible transmittance of the Ga-doped CuS films was in the range of 61–77.1%. Importantly, the near-infrared (NIR) shielding performance of the films can be tuned by adjusting the concentration of the Ga dopant. The NIR shielding value of the optimal Ga-doped CuS film was 72.4%, which was approximately 1.5 times as high as that of the pure CuS film. This can be ascribed to the enhanced plasmonic NIR absorption that resulted from an increase in the hole concentration after doping with Ga3+ ions. In the thermal performance test, the Ga-doped CuS film lowered the interior temperature of the heat box by 9.1 °C. Therefore, the integration of good visible transmittance and high NIR shielding performance make the Ga-doped CuS nanocrystals a promising candidate for energy-efficient window coatings. [ABSTRACT FROM AUTHOR]

In the current paper, copper sulfide nanotubes have been successfully synthesized via the green, simple, and effective gamma-radiolysis method without adding any capping or reducing agents. The structural and morphological characteristics of the as-prepared CuS nanotubes were investigated by X-ray diffraction (XRD), N2 adsorption-desorption measurements at 77 K, transmission electron microscopy (TEM), and ultraviolet-visible (UV-vis) spectroscopy, which all demonstrated the formation of pure CuS covellite phase with tubular morphology. The synthesized CuS nanotubes possessed not only high activity towards the reduction of both cationic (methylene blue) and anionic (Congo red) dyes in the presence of NaBH4 but also exhibited excellent reusability. In addition, the pseudo-first-order kinetic model represented the reduction of MB very well, and the value of the normalized rate constant (2.4 × 10−2 s−1 mg−1) was higher than those of other solid catalysts reported in the literature. Ultimately, CuS nanotubes were found to have a broad-spectrum microbicidal action against the common microbiota, such as Gram-positive (exemplified by Bacillus subtilis and Staphylococcus aureus), Gram-negative bacteria (exemplified by Pseudomonas aeruginosa and Escherichia coli), yeast (exemplified by Candida albicans), and plant pathogenic fungi (exemplified by Aspergillus niger). [ABSTRACT FROM AUTHOR]