Facile synthesis and electrochemical properties of Fe2SeS for lithium ion batteries

•Pure Fe2SeS is synthesized by facile solid-state reaction.•Electrochemical properties of Fe2SeS are investigated as an anode material.•Only one step reaction occurs during both charge and discharge process.•Fe2SeS has higher capacity and better cycle performance than FeS and FeSe.

Fe2SeS is successfully synthesized by facile solid-state reaction and the electrochemical investigation of Fe2SeS as anode for lithium ion batteries is reported for the first time. Fe2SeS deliverers a large initial discharge capacity of 471 mAh g−1. The initial coulombic efficiency (92.56%) is higher than most of double-anion compounds reported previously. It is unexpected to find that Fe reacts simultaneously with Li2S and Li2Se to reform Fe2SeS during charging process, which is different from most double-anion compounds.