Self-wrinkled graphene as a mechanical buffer: A rational design to boost the K-ion storage performance of Sb2Se3 nanoparticles

Design a strategy to relieve the huge volume expansion of high-capacity anode materials for alkali ion batteries is still a challenge. Herein, the self-wrinkled reduced graphene oxide (RGO) sheets are employed as a mechanical buffer to release the mechanical stress and retard the volume expansion of Sb2Se3-based anode material for K-ion storage. By using hydrothermal reaction and followed selenylation process, the Sb2Se3 nanoparticles ( < 50 nm) are in situ encapsulated into the self-wrinkled RGO sheets. Due to the high elasticity of the self-wrinkled graphene to accommodate the volume expansion of Sb2Se3 nanoparticles during electrochemical reaction with K+, an enhanced K storage performance of the Sb2Se3@RGO composite is obtained, with a reversible capacity of 391.4 mAh g(-1) at 100 mA g(-1) and a rate capacity of 203.4 mAh g(-1) at 500 mA g(-1) after 460 cycles.