N-doped carbon-confined SnSe2 nanoparticles as high-performance anode for lithium ion batteries

Tin diselenide (SnSe2) with high theoretical capacity is regarded as a potential anode material for lithium ion batteries. Nevertheless, it suffers from serious volume change during cycling and internal low conductivity, which damages its performance. Here, nitrogen-doped carbon-confined SnSe2 nanoparticles (SnSe2@N-C) were designed to resolve above defects. The SnSe2 particles were nanosized and anchored in carbon matrix, thus effectively restraining volume expansion and enhancing the electric conductivity and ion diffusivity. As-obtained SnSe2@N-C exhibits an initial discharge capacity of 812.7 mAh g(-1) at 0.1 A g(-1), high reversible capacity of 403.7 mAh g(-1) at 0.5 A g(-1) after 300 cycles and superior rate capacity (303.5 mAh g(-1) even at 3 A g(-1)). This strategy may provide an inspiration to enhance electrochemical performances of metal selenide materials for lithium ion batteries.