Graphene-Wrapped ZnMn₂O₄ Nanoparticles with Enhanced Performance as Lithium-Ion Battery Anode Materials

Abstract

ZnMn 2 O 4 nanoparticles (NPs) wrapped by reduced graphene oxide (rGO) were fabricated via a two-step solvothermal method and used as an anode material for lithium-ion batteries (LIBs). Compared to pure ZnMn 2 O 4 , the ZnMn 2 O 4 NPs/rGO composites deliver higher capacities of 1230 mAh g −1 and 578 mAh g −1 after 200 cycles at a current density of 100 mA g −1 and 500 mA g −1 , respectively. The enhanced electrochemical performance of ZnMn 2 O 4 NPs/rGO composites is mainly attributed to a distinctive structure (ZnMn 2 O 4 NPs surrounded by flexible rGO), which can promote the diffusion of Li + , accelerate the transport of electrons and buffer volume expansion during the Li + insertion/extraction process. Furthermore, the rGO sheets can effectively prevent the agglomeration of ZnMn 2 O 4 NPs, thus, improving structural stability of the composites. The excellent electrochemical performance indicates that such ZnMn 2 O 4 NPs/rGO composite structure has a great potential for high-performance LIBs.