Extrinsic-Structured Bimetallic-Phase Ternary Metal Phosphorus Trisulfides Coupled with N-Doped Graphitized Carbon for Superior Electrochemical Lithium Storage

The exploration of advanced electrode materials through rational structure/phase design is the key to develop high-performance rechargeable batteries. Herein, ternary metal phosphorus trisulfides (NiCoPS3) with a bimetallic phase and an extrinsic structure of nanodots combined with nitrogen-doped graphitized carbon (NC) are developed for lithium-ion batteries. The designed NiCoPS3/NC holding a nanocube-like morphology shows a set of structural/compositional advantages as lithium-ion battery anodes including high electrical conductivity, low ion diffusion barrier, improved theoretical lithium storage capacity, and relieved lithiation stress, which are confirmed by characterizations and density functional theory calculations. As a consequence, the NiCoPS3/NC electrode displays superior comprehensive lithium storage performance, e.g., high reversible capacity (991 mAh g(-1) at 0.1 A g(-1)), excellent cycling stability (up to 1200 cycles at 2 A g(-1) and 2000 cycles at 5 A g(-1) with respective capacity retention of over or nearly 100%), and good rate capability (58.4% capacity retention after a current change from 0.1 to 5 A g(-1)), representing the best comprehensive battery performance in MPS3-based anodes to date.

Automated summary

The NiCoPS3/NC electrode designed with a nanocube-like morphology exhibits superior comprehensive lithium storage performance, including high reversible capacity, excellent cycling stability, and good rate capability, representing the best comprehensive battery performance in MPS3-based anodes to date.