A Versatile Pyramidal Hauerite Anode in Congeniality Diglyme‐Based Electrolytes for Boosting Performance of Li‐ and Na‐Ion Batteries

For the first time, environmentally friendly sulfur‐rich pyramidal MnS 2 synthesized via a single‐step hydrothermal process is used as a high‐performance anode material in Li‐ion and Na‐ion batteries. The superior electrochemical performance of the MnS 2 electrode along with its high compatibility with ether‐based electrolytes are analyzed in both half‐ and full‐cell configurations. The reversible capacities of ≈84 mAh g −1 and ≈74 mAh g −1 at a current density of 50 mA g −1 are retained in the Li‐ion and Na‐ion full‐cells, respectively, over 200 cycles with excellent capacity retentions. Moreover, important findings regarding activation processes in the presence of a new phase transition and protective electrolyte interphase layer are revealed using ab initio density function theory calculation and in situ potentio‐electrochemical impedance spectroscopy. The detailed complex redox mechanism of MnS 2 in Li/Na half‐cells is also elucidated by ex situ X‐ray photoelectron spectroscopy.