MoS2@SnS heterostructure for sodium-ion storage with enhanced kinetics

Layered metal sulphides are promising anode materials for sodium ion batteries (SIBs) and capacitors owing to their distinctive crystal structure and large interlayer spacing, suitable for Na+ insertion/extraction. However, low electronic conductivity, sluggish ion transfer and large volume variation of metal sulphides during sodiation/desodiation processes have hindered their practical application. In this work, we report the construction of walnut-like core-shell MoS2@SnS composite as anode for SIBs with high capacity, remarkable rate and cycling stability. Experimental and first principles density functional theory (DFT) calculations reveal that the enhanced electrochemical performances can be mainly ascribed to boosted charge transfer and ion diffusion capability at heterostructure interface driven by a self-building internal electric field. Our findings herein may pave the way to the development of novel composite electrode materials for beyond lithium-ion batteries and capacitors.