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Abstract Despite large theoretical energy densities, metal‐sulfide electrodes for energy storage systems face several limitations that impact the practical realization. Here, we present the solution‐processable, room temperature (RT) synthesis, local structures, and application of a sulfur‐rich Mo₃S₁₃chalcogel as a conversion‐based electrode for lithium‐sulfide batteries (LiSBs). The structure of the amorphous Mo₃S₁₃chalcogel is derived throughoperandoRaman spectroscopy, synchrotron X‐ray pair distribution function (PDF), X‐ray absorption near edge structure (XANES), and extended X‐ray absorption fine structure (EXAFS) analysis, along with ab initio molecular dynamics (AIMD) simulations. A key feature of the three‐dimensional (3D) network is the connection of Mo₃S₁₃units through S−S bonds. Li/Mo₃S₁₃half‐cells deliver initial capacity of 1013 mAh g⁻¹during the first discharge. After the activation cycles, the capacity stabilizes and maintains 312 mAh g⁻¹at a C/3 rate after 140 cycles, demonstrating sustained performance over subsequent cycling. Such high‐capacity and stability are attributed to the high density of (poly)sulfide bonds and the stable Mo−S coordination in Mo₃S₁₃chalcogel. These findings showcase the potential of Mo₃S₁₃chalcogels as metal‐sulfide electrode materials for LiSBs. 

Disordered aggregated porous nanoparticles of KCMS are highly efficient and have exceptionally high sorption capacity in removing Ag⁺and Pb²⁺following the exchange of K⁺and Co²⁺ions bonded electrostatically and covalently in KCMS, respectively. 

Abstract Chalcogel represents a unique class of meso‐ to macroporous nanomaterials that offer applications in energy and environmental pursuits. Here, the synthesis of an ion‐exchangeable amorphous chalcogel using a nominal composition of K₂CoMo₂S₁₀(KCMS) at room temperature is reported. Synchrotron X‐ray pair distribution function (PDF), X‐ray absorption near‐edge structure (XANES), and extended X‐ray absorption fine structure (EXAFS) reveal a plausible local structure of KCMS gel consisting of Mo⁵⁺₂and Mo⁴⁺₃clusters in the vicinity of di/polysulfides which are covalently linked by Co²⁺ions. The ionically bound K⁺ions remain in the percolating pores of the Co–Mo–S covalent network. XANES of Co K‐edge shows multiple electronic transitions, including quadrupole (1s→3d), shakedown (1s→4p + MLCT), and dipole allowed 1s→4p transitions. Remarkably, despite a lack of regular channels as in some crystalline solids, the amorphous KCMS gel shows ion‐exchange properties with UO₂²⁺ions. Additionally, it also presents surface sorption via [S∙∙∙∙UO₂²⁺] covalent interactions. Overall, this study underscores the synthesis of quaternary chalcogels incorporating alkali metals and their potential to advance separation science for cations and oxo‐cationic species by integrating a synergy of surface sorption and ion‐exchange.