Mo <sub>3</sub> S <sub>13</sub> Chalcogel: A High‐Capacity Electrode for Conversion‐Based Li‐Ion Batteries
Taohedul Islam, Subrata Chandra Roy, Sahar Bayat, Misganaw Adigo Weret, Justin M. Hoffman, K.R.P.M. Rao, Conrad Sawicki, Jing Nie, Robiul Alam, Oluwaseun Oketola, Carrie L. Donley, Amar Kumbhar, Renfei Feng, Kamila M. Wiaderek, Chad Risko, Ruhul Amin, Saiful M. Islam, Saiful M. Islam
Abstract
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 Mo 3 S 13 chalcogel as a conversion‐based electrode for lithium‐sulfide batteries (LiSBs). The structure of the amorphous Mo 3 S 13 chalcogel is derived through operando Raman 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 Mo 3 S 13 units through S−S bonds. Li/Mo 3 S 13 half‐cells deliver initial capacity of 1013 mAh g −1 during the first discharge. After the activation cycles, the capacity stabilizes and maintains 312 mAh g −1 at 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 Mo 3 S 13 chalcogel. These findings showcase the potential of Mo 3 S 13 chalcogels as metal‐sulfide electrode materials for LiSBs.