Designing Hierarchical Structure Based on Multi-Phase Metal Sulfides Towards Superb and Safe Energy Storage

The extended usages of lithium ion batteries (LIBs) and sodium ion batteries (SIBs) have confronted with the dilemma of lacking suitable Li + /Na + reservoirs. In this context, a hierarchical structure ( Bi 2 S 3 @CoS 2 @C ) of multi-phase metal sulfides with N, S-doped carbon protector is rationally constructed, which shows high pyridinic-N as well as pyrrolic-N proportions. As LIBs anode, Bi 2 S 3 @CoS 2 @C electrode shows an initial discharge capacity of 1226.4 mAh g -1 . Even after 229 cycles, a high discharge capacity of 1059.1 mAh g -1 is still retained. As SIBs anode, this electrode shows an initial discharge capacity of 750.4 mAh g -1 , with an extremely-low capacity decay rate of 0.008% per cycle during long-term cycling at 2 A g -1 . In addition, the cycling and rate performances comparisons confirm its comparative or even better rate property than many other metal sulfides. In general, this electrode holds favorable Li + /Na + storage actions and related reaction kinetics. Of note, using Bi 2 S 3 @CoS 2 @C electrode promotes the thermal safety, via delaying the emerging of maximum thermal runaway temperature. Thus, this work may be encouraging for designing multi-phase metal sulfides based hierarchical structure towards superb and safe energy storage.