SnF₂-Doped Cs₄PbBr₆ Glass Ceramic as a High-Performance Anode for Li-Ion Batteries

Halide perovskite crystal glass ceramics show excellent electrochemical performance as glass anodes. Halide perovskite crystal glass ceramics can not only supply storage location by an open network and perovskite but also stabilize ion channels for lithium by the open network structure, just as [GeOδ] and [BOγ] units and so on. But in the long-running charge and discharge process, the specific capacity is not exactly so well. Herein, a SnF2-doped Cs4PbBr6 halide perovskite crystal glass ceramic was prepared by the traditional melt-quenching method. SnF2 as a notable doped material could increase lithium storage sites in the halide perovskite crystal glass ceramic. The prepared SnF2-GC is divided into two layers: one is a pure phase of crystals (named FLI) and the other is a bulk of mixed phase (named FLII). FLII has shown better electronic performance. The specific capacity of FLII achieved is 773 mAh g–1 at 0.5 A g–1, except that Sn participated in the charging and discharging process. F ions could also improve the stability of FLII. The doping of divalent metal fluorides is a better step for the application of halide perovskite structure glass ceramic materials in the field of batteries.