Bead-milling and recrystallization from natural marmatite to Fe-doping ZnS-C materials for lithium-ion battery anodes

Abstract

The use of ZnS as anode materials in lithium-ion batteries (LIBs) has exhibited particular advantages of high theoretical capacity (962.3 mAh•g−1) and low discharge platform. Compared to chemosynthetic ZnS, natural marmatite (Fe-doped ZnS) can be regarded as a promising anode material with higher conductivity and lower cost. In this work, Fe-doped ZnS composites-1/2/3 (FZC-1/2/3) were synthesized by three methods: bead-milling, bead-milling with Super P, and solid-phase recrystallization (SPR) after bead-milling with Super P, respectively. FZC-3 exhibited high initial discharge and charge capacities of 1031.2 and 825.6 mAh g−1, respectively. Even after 200 cycles, it retained a charge capacity of 672.0 mAh g−1 at 0.2 A g−1, with a coulombic efficiency (CE) of 99.6%. Even at high specific currents of 2.0 and 10.0 A g−1, the maintained discharge capacities of 555.1 and 183.2 mAh g−1 after 1000 cycles, respectively, and the CE was almost 100%. In addition, phase transition of Fe and aggregation structure were characterized to explore the improvement of cycling stability. Furthermore, the first-principles calculation was performed to investigate Fe-doped ZnS and S-doped carbon. This work will provide a simple and practical method to produce marmatite-based anodes for LIBs.