Chalcogenide Research Articles

Kirkendall Effect-Driven Reversible Chemical Transformation for Reconfigurable Nanocrystals.

The potential universality of chemical transformation principles makes it a powerful tool for nanocrystal (NC) synthesis. An example is the nanoscale Kirkendall effect, which serves as a guideline for the construction of hollow structures with different properties compared to their solid counterparts. However, even this general process is still limited in material scope, structural complexity, and, in particular, transformations beyond the conventional solid-to-hollow process. We demonstrate in this work an extension of the Kirkendall effect that drives reversible structural and phase transformations between metastable metal chalcogenides (MCs) and metal phosphides (MPs). Starting from Ni3S4/Cu1.94S NCs as the initial frameworks, ligand-regulated sequential extractions and diffusion of host/guest (S2-/P3-) anions between Ni3S4/Cu1.94S and Ni2P/Cu3P phases enable solid-to-hollow-to-solid structural motif evolution while retaining the overall morphology of the NC. An in-depth mechanistic study reveals that the transformation between metastable MCs and MPs occurs through a combination of ligand-dependent kinetic control and anion mixing-induced thermodynamic control. This strategy provides a robust platform for creating a library of reconfigurable NCs with tunable compositions, structures, and interfaces.

Dual-functional MnS nanomaterials: Efficient adsorbent for phosphate removal and sonocatalyst for textile dye degradation

Naturally abundant, environmentally friendly alternatives for replacing the expensive lanthanum-based phosphate removal technique are sought after. Solocatalysis is an emerging area for water remediation. This study introduces a dual-functional MnS nanomaterial for removing phosphate ions and Congo Red textile dye. MnS nanomaterials were synthesized via a hydrothermal route. Batch adsorption experiments revealed a phosphate adsorption capacity of 160.73 mg P/g, commendable for adsorbent in its bare form. Thermodynamic parameters of the process indicated a spontaneous, exothermic process, confirming favourable adsorption. FTIR analysis confirmed the adsorption mechanism, which includes electrostatic attraction, surface complexation, and ion exchange. MnS maintained its adsorption capacity despite competing ions, demonstrating a selective affinity for phosphate ions. MnS showed high sonocatalytic efficiency, degrading Congo Red dye within 10 min of ultrasonic irradiation. The degradation mechanism of Congo Red dye in the sonocatalytic process is proposed. This novel metal chalcogenide material exhibits exceptional affinity for phosphate ions and Congo Red dye molecules, surpassing La-based adsorbents in efficacy. The results suggest that MnS nanomaterials are promising for practical applications in phosphate removal and textile dye degradation from wastewater.

The Application of Sulfur–Metal Mass Ratios in Metal Sulfides in Assessing Prospects for Deep Metallogeny: A Case Study of the Tongshan Copper Deposit in Heilongjiang Province, Northeast China

Sulfur–metal mass ratios (SMMRs) between sulfur and metal elements (Cu, Pb, Zn, Ag, Fe, etc.) in metal sulfides are fixed in idealized compositions, so they should have a relatively fixed proportion in terms of mass without considering the presence of structural defects such as vacancies or substitution elements. Rock bodies with an SMMR of S far greater than the common metal sulfides may contain additional sulfides of other metals. We studied the Tongshan copper deposit in NE China and calculated the mass transfer of various elements in drill hole ZK611 samples. The data show a S influx of 7160 g/t, a Cu influx of 5469 g/t, and an Fe influx of 8796 g/t in the Cu ore body. Below the Cu ores, the average influx is 18,600 g/t of S, 650 g/t of Cu, and 5360 g/t of Fe, which provides an SMMR far above common mineral sulfide values. Further studies indicated that this rock unit contains fine-grained sphalerite and galenite, and when Zn and Pb are included in the rock SMMR calculations, values closer to the mineral sulfides emerge. These results imply that the coordinating balance relationship of S content with Fe and other ore-forming metals could provide direct information for assessing metallogenic prospects.

High-performance Bi2S3 photodetector based on oxygen-mediated defect engineering and its wafer-scale fast fabrication

Bi2S3 with a 2D van der Waals structure has attracted much attention due to its high conductivity, large absorption coefficient, and environmental friendliness. The preparation of tunable optoelectronic devices can be realized by exploiting and tuning Bi2S3 intrinsic defects. In this work, a simple and rapid method for the preparation of bismuth sulfide thin films and successfully prepare Bi2S3 with sulfur vacancies (Svac) (LA-Bi2S3) and oxygen passivated (Svac) (AP-Bi2S3) was presented. The defect state difference of the two devices leads to exhibit different optoelectronic properties. Under 638 nm and 1310 nm illuminations, the LA-Bi2S3 photodetectors exhibit responsivities of up to 2250 and 3.6 mA/W and detectivities of 1.69 × 1012 and 2.6 × 109 cm·Hz1/2 W−1, while the AP-Bi2S3 photodetectors have ultra-fast on/off speeds of 1 ms and 8 ms, and on/off ratio up to 3 × 103. The preparation method of the tunable optoelectronic devices gives a new avenue for defect tuning in metal sulfides and for the preparation and application of optoelectronic devices.

Pressure-induced band gap enhancement and temperature-dependent thermoelectric characterization of semiconducting Transition Metal Chalcogenides LiMS (M = Cu, Ag)

The first principles study of Transition Metal Chalcogenides LiMS (M = Cu, Ag) has been conducted utilizing the concepts of Density Functional Theory (DFT). Both the compounds possess a cubic structure with space group F-43m. The mechanical stability of LiCuS and LiAgS has been predicted based on the values of elastic tensor. These Chalcogenides possess an interesting electronic band structure which reveals their semiconducting nature with a direct band gap. The electronic structure is further subjected to high pressure and the changes in band gap are deeply observed. For these materials, the changes in band gap in response to applied pressure suggest the possibility of their use in band gap engineering. The phonon curves are investigated over the Brillouin zone's high symmetry directions which reveal the lattice dynamical stability of the presently studied compounds. Moreover, the atoms present at different positions inside a crystal lattice exhibit vibrations of different intensities and in different directions which have been studied through the Eigenvector representations. The thermoelectric properties of LiCuS and LiAgS have been characterized using Boltzmann's theory over the range of temperature between 100 K and 1600 K. The calculated thermoelectric parameters reveal the high thermoelectric efficiency of these materials with excellent values of the figure of merit. The interesting properties of ternary Chalcogenides LiMS (M = Cu, Ag) make them promising candidates for thermoelectric applications.

Electrochemical biosensor based on copper sulfide/reduced graphene oxide/glucose oxidase construct for glucose detection

Due to the current increase in the number of people suffering from diabetes worldwide, how to monitor the blood glucose level in the human body has become an urgent problem to be solved nowadays. The electrochemical sensor method can be used for real-time glucose monitoring due to its advantages of real-time monitoring capability and high sensitivity. Reduced graphene oxide (rGO) has great potential for application in the field of sensors due to its advantages of large specific surface area, high stability, and good electrical and thermal conductivity. Meanwhile, the synergistic effect between two-dimensional transition metal sulfides and graphene can improve the electrochemical performance of materials due to their similar mechanical flexibility and strength. This article uses flake graphite, copper sulfate, and glucose oxidase (GOx) as raw materials to prepare CuS/rGO/GOx/GCE electrodes, and explores the performance of electrode electrocatalysis for glucose. The results showed that the prepared sensor was characterized by a low detection limit (1.75 nM) and a wide linear range (0.1–100 mM) for glucose detection, displaying a good overall detection performance, and its sensing mechanism and dynamic process were also investigated. In addition, the sensor has outstanding selectivity, anti-interference, repeatability, reproducibility and practicality.

An Electrochemical Study of the Effect of Sulfate on the Surface Oxidation of Pyrite.

Pyrite is one of the most abundant metal sulfide tailings and is susceptible to oxidation, yielding acidic mine drainage (AMD) that poses significant environmental risks. Consequently, the exploration of pyrite surface oxidation and the kinetic influencing factors remains a pivotal research area. Despite the oxidation of pyrite producing a significant amount of sulfate (SO42-), a comprehensive investigation into its influence on the oxidation process is lacking. Leveraging pyrite's semiconducting nature and the electrochemical intricacies of its surface oxidation, this study employs electrochemical techniques-cyclic voltammetry (CV), Tafel polarization, and electrochemical impedance spectroscopy (EIS)-to assess the effect of SO42⁻ on pyrite surface oxidation. The CV curve shows that SO42- does not change the fundamental surface oxidation mechanism of pyrite, but its redox peak current density decreases with the increase in SO42-, and the surface oxidation rate of pyrite decreases. The possible reason is attributed to SO42- adsorption onto pyrite surfaces, blocking active sites and impeding the oxidation process. Furthermore, Tafel polarization curves indicate an augmentation in polarization resistance with elevated SO42- concentrations, signifying heightened difficulty in pyrite surface reactions. EIS analysis underscores an increase in Weber diffusion resistance with increasing SO42⁻, indicating that the diffusion of Fe3+ to the pyrite surface and the diffusion of oxidized products to the solution becomes more difficult. These findings will improve our understanding of the influence of SO42- on pyrite oxidation and have important implications for deepening the understanding of surface oxidation of pyrite in the natural environment.

Rational Design of 3D Hierarchical Fe3S4 for Superior Sodium‐Ion Battery Anode Material

AbstractAmong various transition metal sulfides, iron‐based sulfides have attracted wide attention due to their abundant resources, low cost, and non‐toxicity, showing considerable research value in the field of secondary batteries. Thereinto, Fe3S4 has a high theoretical specific capacity of 785 mAh g−1. However, at present, the research related to Fe3S4 anode for sodium‐ion batteries (SIBs) is still in its infancy, and it also suffers from severe volume expansion and limited preparation. Therefore, to further boost its sodium storage potential, the Fe3S4@rGO composite with hierarchical structure and carbonaceous network is proposed in this study. Beneficial from the ingenious hierarchitectures and flexible graphene coating, the Fe3S4@rGO anode exhibits outstanding sodium storage performance, which can deliver a high capacity of 603 mAh g−1 after 1500 cycles with a superior capacity retention of 98%. The micron flower‐like structure composed of 2D nanosheets can provide sufficient active sites and promote the rapid transport of Na+. Meanwhile, the 3D interconnected graphene carbon network makes a crucial contribution to alleviating volume changes and enhancing electrical conductivity. This work reveals the application potential of Fe3S4 as an anode electrode for SIBs and provides available insights for the development of other electrode materials.

Rapid and controllable microwave synthesis of nickel cobalt sulfide electrodes for high-performance asymmetric supercapacitors

The efficient and controllable synthesis method of high-performance energy storage electrode materials is crucial for advancing the development of energy storage technologies. Herein, by leveraging microwave heating technology in the sulfidation of nickel cobalt MOF, we effectively enhanced the efficiency of the synthesis process. Notably, sulfidation time emerged as a pivotal factor in tuning the crystalline phase structure and conductive properties of the material, leading to the successful development of NCS2 electrode material with a unique structure through optimized sulfidation conditions. Electrochemical performance tests of the NCS2 material revealed exceptional results; it exhibited a specific capacity of 1311 Fg[Formula: see text] at a current density of 1 Ag[Formula: see text] and retained 73.4% of its initial capacity when the current density increased to 10 Ag[Formula: see text], demonstrating outstanding rate performance. The composite NCS2//AC supercapacitor exhibits an energy density of 24.2 Whkg[Formula: see text] at power density of 800 Wkg[Formula: see text], even though after 1000 consecutive charge-discharge cycles, the capacity retention rate remained high at 77.1%, validating the exceptional stability and reliability of the NCS2 material during cycling. This work employs microwave sulfidation for the rapid and controlled synthesis of nickel cobalt sulfides, providing a green and efficient synthetic strategy for metal sulfide active materials.

Construction of heterojunction based on Nd2S3 and tin dioxide for rapid detection of ethanol

The gas-sensing properties of Nd2S3 have not been previously explored. In this study, a novel composite material comprising rare-earth metal sulfide (Nd2S3) and metal oxide (SnO2) was successfully prepared using a two-step hydrothermal method for the rapid detection of ethanol. Characterization results revealed that the morphology and specific surface area of Nd2S3-SnO2 remained largely unchanged after composite formation. However, the built-in electric field established between Nd2S3 and SnO2 significantly enhanced carrier transport and separation. Additionally, the introduction of extra oxygen vacancies increased the content of chemisorbed oxygen, providing more active sites for ethanol molecules, thereby improving the gas-sensing performance. The Nd2S3-SnO2 sensor demonstrated extremely high detection accuracy (R2=0.9965) over the 20–300 ppm ethanol concentration range, with response/recovery time of 8/274 s at 100 ppm ethanol concentration and response value of 93. It also possesses excellent selectivity to ethanol, long-term stability and reversibility. This work represents a preliminary exploration of the gas-sensing properties of Nd2S3 and its underlying mechanisms through the construction of a heterojunction structure between metal sulfide and metal oxide.

High entropy 2D metals sulfides: Fast synthesis, exfoliation and electrochemical activity in overall water splitting at alkaline pH

Novel simple and efficient method for synthesis of 2D high entropy sulfides of iron group metals is described. The method utilizes inorganic salts as precursors and CS2 as a sulfurizing agent, which makes it possible to achieve high entropy composition through combination of freezing of the precursor solution, subsequent freeze-drying step, sulfurization, and exfoliation in liquid nitrogen. The created material was investigated as a catalyst for electrochemical water splitting at different pH. Measured overpotentials at 10 and 100 mA*cm−2 current densities for hydrogen evolution reaction (HER) were found to be 49 and 315 mV respectively, while for oxygen evolution reaction (OER) theoverpotentials required for reaching 10 and 100 mA*cm−2 current densities were 370 and 591 mV respectively, both in 1 M KOH solution. The Tafel slopes for HER were found to be 235, 105, and 111 mV/dec in basic, neutral, and acidic conditions, respectively, while only 63 mV/dec for OER in basic conditions. The calculated values of the turnover frequency were 0.62 s−1 for HER and 0.10 s−1 for OER. We also confirmed the key role of high entropy in the catalytic activity of the material by excluding individual elements from the composition of the HES.

Hierarchical Nanowire Host Material for High‐Areal‐Capacity All‐Solid‐State S/SeS2 Batteries

AbstractAll‐solid‐state sulfur batteries (ASBs) suffer from electrical and ionic conduction problems due to the insulating sulfur. By comparing three host materials with different structural characteristics, herein, carbon nanotubes (CNTs) decorated with a conductive metal sulfide (CoMoS2@CNT) is demonstrated, designed to host sulfur and exchange both Li‐ions and electrons, effectively. In this hierarchical wire structure, porous CoMoS2 nanosheets form close interfaces with sulfur, and the CNT core directly transfers electrons to the sulfur‐impregnated CoMoS2. Simultaneously, the solid electrolyte positioned on the outer region of the nanowire material ensures facile Li‐ion conduction to the sulfur‐impregnated CoMoS2. An ASB featuring a CoMoS2@CNT host material with a sulfur loading of 3 mg cm−2 exhibits a high‐areal‐capacity of 4.5 mAh cm−2 at a current density of 2.5 mA cm−2, while retaining 79.4% of its initial capacity after 300 cycles. When sulfur is replaced with SeS2 to further reinforce the charge conduction properties, all‐solid‐state SeS2 batteries (ASeS2Bs) with an extremely high‐areal‐capacity of 16.3 mAh cm−2 retain 99.3% of their initial capacities after 60 cycles at 60 °C. This study provides guidelines for the design principles of cathode composites for the ASBs and ASeS2Bs through multiangle comparative analysis.

Accumulated Copper Tailing Solid Wastes with Specific Compositions Encourage Advances in Microbial Leaching

Against the backdrop of the increasing copper demand in a low-carbon economy, this work statistically forecasted the distribution of China’s copper tailings for the first time, and then characterized them as finely crushed and low-grade mining solid wastes containing copper mainly in the form of chalcopyrite, bornite, covelline, enargite and chalcocite based on available research data. China is the globally leading refined copper producer and consumer, where the typical commercial-scale bioleaching of copper tailings is conducted in the Dexing, Zijinshan and Jinchuan mining regions. And these leaching processes were compared in this study. Widely used chemolithoautotrophic and mesophilic bacteria are Acidithiobacillus, Leptospirillum, Acidiphilium, Alicyclobacillus and Thiobacillus with varied metal resistance. They can be used to treat copper sulfide tailings such as pyrite, chalcopyrite, enargite, chalcocite, bornite and covellite under sufficient dissolved oxygen from 1.5 to 4.1 mg/L and pH values ranging from 0.5 to 7.2. Moderate thermophiles (Acidithiobacillus caldus, Acidimicrobium, Acidiplasma, Ferroplasma and Sulfobacillus) and extreme thermophilic archaea (Acidianus, Metallosphaera, Sulfurococcus and Sulfolobus) are dominant in leaching systems with operating temperatures higher than 40 °C. However, these species are vulnerable to high pulp density and heavy metals. Heterotrophic Acidiphilium multivorum, Ferrimicrobium, Thermoplasma and fungi use organic carbon as energy to treat copper oxides (malachite, chrysocolla and azurite) and weathered sulfides (bornite, chalcocite, digenite and covellite) under a wide pH range and high pulp density. We also compared autotrophs in a planktonic state or biofilm to treat different metal sulfides using various sulfur-cycling enzymes involved in the polysulfide or thiosulfate pathways against fungi that produce various organic acids to chelate copper from oxides. Finally, we recommended a bioinformatic analysis of functional genes involved in Fe/S oxidization and C/N metabolism, as well as advanced representation that can create new possibilities for the development of high-efficiency leaching microorganisms and insight into the mechanisms of bioleaching desired metals from complex and low-grade copper tailings.

Promoting elemental mercury immobilization performance from smelting flue gas over a wide temperature range via cobalt-doped copper sulfide adsorbents

Copper sulfide (CuS) sorbent exhibits great potential for gaseous elemental mercury (Hg0) decontamination, but it still suffers from a narrow operating temperature. Therefore, designing advanced CuS sorbents that have a high activity level for capturing Hg0 and thermal stability at a high temperature range is challenging. Herein, we propose a metal doping strategy to fabricate a bimetallic sulfide adsorbent. Benefiting the unique structure and composition, a mesoporous structure and an abundance of unsaturated sulfur sites ensure that CuxCo(1–x)Sy provides a desirable level of adsorption for Hg0. The experimental results indicate the optimum Co doping mass concentration of 5 %. The Cu0.95Co0.05Sy not only performs satisfactory Hg0 adsorption at elevated temperatures (Hg0 average adsorption efficiency of over 97.3 %, Hg0 average adsorption rate of over 2.7 μg/g/min), but also presents an exciting regeneration and recycle performance (a Hg0 adsorption efficiency of over 94 % after 10 cycles). The adsorption capacity of Cu0.95Co0.05Sy at the breakthrough threshold of 25 % reaches 5.22 mg/g, surpassing most of metal sulfide sorbents for Hg0 immobilization at 150 °C. As far as Hg0 adsorption is concerned, the composition of typical smelting flue gases has almost no effect. According to further studies, unsaturated coordination short-chain sulfur (S22−) sites are essential for adsorption of Hg0 and are capable of directly forming α-HgS from Hg0. In both the contrast experiment and density functional theory calculations, the cobalt doping strategy enhances the thermal stability of the active S22− ligand and the Hg0 adsorption properties. This study not only provide a prospective adsorbent for Hg0 sequestration at wide temperature range, but also explores a method of utilizing gaseous contaminants for resource utilization.

Coordination Compound Derived Co9S8 Supported on Nitrogen and Sulfur Co‐Doped Porous Carbon for Oxygen Reduction Reaction

AbstractCobalt sulfide, a class of metal chalcogenide with tunable electronic structure and component distribution, has attracted considerable interest in renewable energy conversion and utilization. In this work, we report a facile, efficient and scalable method to synthesize Co9S8 supported on nitrogen and sulfur co doped porous carbon (Co9S8/N,S‐PC) hybrid from the annealing treatment of a coordination compound assembled by 2‐mercaptobenzimidazole, 4,4‐bipyridine and cobalt salt. The heteroatom of organic ligand could efficiently tune the electronic properties of Co9S8 nanoparticles and well‐designed carbon. Meanwhile the interaction of organic ligands provides a platform for the high dispersion of Co9S8. Owing to the synergetic effect, the Co9S8/N,S‐PC catalyst shows an admirable oxygen reduction reaction (ORR) activity with the E1/2 of 0.804 V vs. RHE, together with good durability, and tolerance to methanol poisoning in alkaline media.

Potentiostatic electrodeposition of copper, indium, and cadmium sulfides for CO2 electroreduction: A path toward sustainable hydrogen generation

This study focuses on the potentiostatic electrodeposition of copper indium and cadmium sulfide (CuS, In2S3, and CdS) thin films on copper substrates, aiming to develop efficient electrocatalysts for the electrochemical reduction of CO2 and sustainable hydrogen generation. Utilizing Cu Kα radiation for X-ray diffraction (XRD) analysis, the crystal structures of the electrodeposited films were confirmed, revealing well-defined crystalline phases. The films exhibited average particle sizes of 55.99 nm for CuS, 50.37 nm for In2S3, and 63.51 nm for CdS. Cyclic voltammetry and chronoamperometry were employed to optimize the deposition parameters, ensuring efficient nucleation and growth of the metal sulfide films. The electrochemical performance of the synthesized electrocatalysts was rigorously tested, demonstrating their potential for CO2 reduction under optimized conditions with the highest efficiency for CdS electrodes. Additionally, the electrodeposited CuS and CdS are of the p-type, and In2S3 is of the n-type semiconductor were studied and verified by the Mott–Schottky test. CuS, In2S3, and CdS were found to have donor and acceptor concentrations (ND) of 1.68 × 106, 1.44 × 105, and 8.9 × 105 cm3, respectively. The photoelectrochemical measurements of the electrodeposited metal sulfides were studied at ambient temperature and under illumination, providing higher photocurrent responses for CdS and demonstrating its strong potential as a photoelectrode material for CO2 reduction. This work underscores the significance of facile electrochemical synthesis methods in developing cost-effective and scalable electrocatalysts, paving the way for their integration into photoelectrochemical systems for green energy applications.

Tellurenated Compounds: Synthesis and Application in Ion Detection and as a Catalyst

AbstractTellurium is now recognized as a ‘technology-critical element’ that is quickly being used in innovative applications. The chemistry of organotellurium ligands has improved rapidly during the last three decades. Because of their enhanced accessibility and the possibility that they would display significantly different properties than their sulfur counterparts, these ligands of heavier chalcogens have sparked considerable attention. The next sections will go through the various tellurium ligands and associated transition-metal complexes. Organochalcogen ligands are exceedingly flexible ligands that may react with nearly any transition metal to form a wide range of compounds, including multidentate ligands.Tellurides of various metals have lately been investigated for potential use in storage devices, solar cells, piezoelectric, medical applications, electronics, photothermal treatment, nanoplatelets, nanocrystals, catalysis, and other fields. Researchers are interested in metal chalcogenide heterostructures because of their improved charge transport and synergistic optoelectronic and catalytic properties. A sensor for various metals based on Te electrodes and a donor ligand are used to generate electrical signals and identify different metals. Due to the scarcity of tellurium, metal telluride nanocrystal heterostructures have received less attention than metal sulfide and metal selenide nanocrystal heterostructures.1 Introduction2 Tellurenated Compounds of Zwitterionic Nature3 Synthesis of Tellurenated Ligands and Complexes4 Catalytic Application and and Suzuki–Miyara Coupling5 Tellurenated Sensors for Metal-Ion Sensing5.1 Tellurium-Ion Detectors5.2 Drawbacks/Catalyst Poisoning5.3 Disadvantages5.4 Advantages and Future Prospects6 Conclusions

Atomic layer deposition of transition metal chalcogenide TaSx using Ta[N(CH3)2]3[NC(CH3)3] precursor and H2S plasma

As a transition metal chalcogenide, tantalum sulfide (TaSx) is of interest for semiconductor device applications, for example, as a diffusion barrier in Cu interconnects. For deposition of ultrathin nanolayers in such demanding 3D structures, a synthesis method with optimal control is required, and therefore, an atomic layer deposition (ALD) process for TaSx was developed. ALD using (tert)-butylimidotris(dimethylamido)tantalum (Ta[N(CH3)2]3[NC(CH3)3]) as the precursor and an H2S-based plasma as the coreactant results in linear growth of TaSx films as a function of the number of cycles for all temperatures in the range 150–400 °C with growth per cycle values between 1.17±0.03 Å and 0.87±0.08 Å. Saturation of the precursor and plasma dose times, established at 300 °C, was reached after 20 and 10 s, respectively. Variation of the table temperature or the plasma composition offers the possibility to tune the film properties. At 300 °C, amorphous TaS3 films were grown, while addition of H2 to the plasma led to polycrystalline TaS2 films. The difference in sulfur content in the films correlates to a change in resistivity, where the least resistive film had the lowest S content.

Amplifying energy storage and production efficiency: Utilizing BaS3: Ni2S3: Sb2S3 synthesized from dithiocarbamate precursors for enhanced and sustainable energy solutions

During this period of increasing energy use, the scientific community and energy stakeholders have been closely monitoring electrochemical energy storage. In an attempt to enhance the functionality of charge storage devices, diethyldithiocarbamate ligand is employed as a chelating agent during the production of the novel BaS3: Ni2S3: Sb2S3. The semiconductor BaS3: Ni2S3: Sb2S3, which was made in an environmentally friendly manner, showed good photoactivity due to its 2.97 eV energy band gap and light absorption. The resultant chalcogenide had an average crystallite size of 19.69 nm and displayed outstanding crystallinity with mixed crystallographic phases. Furthermore, infrared spectroscopy was used to investigate metallic sulfide connections, and the findings indicated that they varied between 500 and 875 cm−1. This chalcogenide featured varied sites for electrochemical reactions due to its morphology. The electrochemical performance of BaS3: Ni2S3: Sb2S3 was assessed using a conventional three-electrode setup. With a specific capacitance of up to 1019.4 F g−1 and a power density of 11931.26 W kg−1, BaS3: Ni2S3: Sb2S3 has proven to be an excellent electrode material for energy storage. This remarkable electrochemical performance was further reinforced by the comparable series resistance (Rs) of 0.57 Ω. During electrocatalysis, the electrode produced an OER overpotential with a Tafel slope of 348 mV and 119 mV dec−1. In contrast, the overpotential and Tafel slope in terms of the HER activity and were 211 mV and 100 mV/dec, respectively.

Structural Changes in Copper Slags During Slow Cooling

The objects of the study were converter slags from the Balkhash copper plant in their initial state and after heat treatment. Using mineralogical and X-ray phase analysis, scanning electron microscopy (SEM), and electron probe microanalysis (EPMA), it was found that the initial converter slag and its thermally treated samples have identical matrices with almost complete coincidence in mineral and phase compositions. The distinguishing feature is the quantitative ratio of mineral components in the slag mass. Almost all of the iron is oxidized and present in the form of fayalite, magnetite, and magnetite, with other elements (silicon, copper, zinc, and aluminum) incorporated into its lattice. The structure of all slag samples indicates an association of sulfur exclusively with copper. Copper in the slags was identified in both metallic and sulfide forms. Slow cooling of the converter slag after its remelting contributes to the reduction in the sulfide–metal suspension in the volume of the melt and its coarsening. During slow cooling, structural changes occur not only in the main oxide part of the slag but also in the polymetallic globules.