Lithium–sulfur (Li–S) batteries are severely hindered by the low sulfur utilization and short cycling life, especially at high rates. One of the effective solutions to address these problems is to improve the sulfiphilicity of lithium polysulfides (LiPSs) and the lithiophilicity of the lithium anode. However, it is a great challenge to simultaneously optimize both aspects. Herein, by incorporating the merits of strong absorbability and high conductivity of SnS with good catalytic capability of ZnS, a ZnS-SnS heterojunction coated with a polydopamine-derived N-doped carbon shell (denoted as ZnS-SnS@NC) with uniform cubic morphology was obtained and compared with the ZnS-SnS2@NC heterostructure and its single-component counterparts (SnS@NC and SnS2@NC). Theoretical calculations, ex situ XANES, and in situ Raman spectrum were utilized to elucidate rapid anchoring-diffusion-transformation of LiPSs, inhibition of the shuttling effect, and improvement of the sulfur electrochemistry of bimetal ZnS-SnS heterostructure at the molecular level. When applied as a modification layer coated on the separator, the ZnS-SnS@NC-based cell with optimized lithiophilicity and sulfiphilicity enables desirable sulfur electrochemistry, including high reversibility of 1149 mAh g–1 for 300 cycles at 0.2 C, high rate performance of 661 mAh g–1 at 10 C, and long cycle life with a low fading rate of 0.0126% each cycle after 2000 cycles at 4 C. Furthermore, a favorable areal capacity of 8.27 mAh cm–2 is maintained under high sulfur mass loading of 10.3 mg cm–2. This work furnishes a feasible scheme to the rational design of bimetal sulfides heterostructures and boosts the development of other electrochemical applications.

Lithium–sulfur (Li–S) batteries have been hindered by the shuttle effect and sluggish polysulfide conversion kinetics. Here, a P‐doped nickel tellurium electrocatalyst with Te‐vacancies (P⊂NiTe2−x) anchored on maize‐straw carbon (MSC) nanosheets, served as a functional layer (MSC/P⊂NiTe2−x) on the separator of high‐performance Li–S batteries. The P⊂NiTe2−x electrocatalyst enhanced the intrinsic conductivity, strengthened the chemical affinity for polysulfides, and accelerated sulfur redox conversion. The MSC nanosheets enabled NiTe2 nanoparticle dispersion and Li+ diffusion. In situ Raman and ex situ X‐ray absorption spectra confirmed that the MSC/P⊂NiTe2−x restrained the shuttle effect and accelerated the redox conversion. The MSC/P⊂NiTe2−x‐based cell has a cyclability of 637 mAh g‐1 at 4 C over 1800 cycles with a degradation rate of 0.0139% per cycle, high rate performance of 726 mAh g‐1 at 6 C, and a high areal capacity of 8.47 mAh cm‐2 under a sulfur configuration of 10.2 mg cm‐2, and a low electrolyte/sulfur usage ratio of 3.9. This work demonstrates that vacancy‐induced doping of heterogeneous atoms enables durable sulfur electrochemistry and can impact future electrocatalytic designs related to various energy‐storage applications.

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This study demonstrates quick and efficient removal of different dyes from wastewater by using MoS2/CuS nanosheet composites (NCs) as adsorbent. The MoS2/CuS NCs are prepared by a facile hydrothermal route, and the composites exhibit high adsorption capacity with 273.23, 432.68, 98.78, and 211.18 mg/g for rhodamine B (RhB), methylene blue (MB), methyl orange (MO), and rhodamine 6G dyes (RhB 6G), respectively. This is ascribed to its high specific surface area (106.27 m2/g) and small mesopores (2.299 nm) which provide numerous adsorption sites and uniform coverage for dye molecules. High adsorption efficiency is obtained for RhB (93.8%), MB (100%), and RhB 6G (84.73%), except for MO (48.9%) at the adsorption equilibrium time at the solution concentration of 80 mg/L. The adsorption of MoS2/CuS NCs can be well described by the pseudo-second-order kinetic model, and the adsorption isotherm at the equilibrium fits well with the Langmuir model. The rapid and efficient adsorption ensures MoS2/CuS NCs to be a broad-spectrum adsorbent for different dye contaminants in water.

Lithium–sulfur (Li–S) batteries featuring high-energy densities are identified as a hopeful energy storage system but are strongly impeded by shuttle effect and sluggish redox chemistry of sulfur cathodes. Herein, annealed melamine foam loaded 2H/1T MoS2 (CF@2H/1T MoS2) is prepared as a multifunctional interlayer to inhibit the shuttle effect, improve redox kinetics, and reduce the charge–discharge polarization of Li–S batteries. The CF@2H/1T MoS2 becomes fragmented structures after assembling the cell, which not only benefits to adsorb and catalyze LiPSs but also to significantly buffer the volume expansion due to a large number of gaps between fragmented structures. Meanwhile, the batteries based on CF@2H/1T MoS2 interlayer delivers high areal capacity of 5.1 mAh cm–2 under high sulfur mass loading of 7.6 mg cm–2 at 0.2 C. Importantly, the experiments of in situ Raman spectra demonstrate that the CF@2H/1T MoS2 can obviously inhibit the shuttle effect by effectively adsorbing and catalyzing LiPSs. This novel design idea and low-cost melamine foam raw material open up a new way for the application of high-energy density Li–S batteries.

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We report a simple one-step hydrothermal strategy for the fabrication of a C-MoS2/rGO composite with both large surface area and high porosity for the use as advanced electrode material in lithium–sulfur batteries. Double modified defect-rich MoS2 nanosheets are successfully prepared by introducing reduced graphene oxide (rGO) and amorphous carbon. The conductibility of the cathodes can be improved through the combination of amorphous carbon and rGO, which could also limit the dissolution of polysulfides. After annealing at different temperatures, it is found that the C-MoS2/rGO-6-S composite annealed at 600 °C yields a noticeably enhanced performance of lithium–sulfur batteries, with a high specific capacity of 572 mAh·g−1 at 0.2C after 550 cycles, and 551 mAh·g−1 even at 2C, much better than that of MoS2-S nanosheets (249 mAh·g−1 and 149 mAh·g−1) and C-MoS2/rGO-S composites (334 mAh·g−1 and 382 mAh·g−1). Our intended electrode design protocol and annealing process may pave the way for the construction of other high-performance metal disulfide electrodes for electrochemical energy storage.