Development of electrode architecture using Sb-rGO composite and CMC binder for high-performance sodium-ion battery anodes

Abstract

Metallic antimony (Sb) is considered as a promising anode material for sodium-ion batteries (SIBs) owing to its high theoretical capacity (660 mAh/g) based on alloying/dealloying reactions with sodium ions. The main issues of Sb, however, are its large volume expansion upon cycling. In this study, we synthesized Sb- reduced graphene oxide (rGO) composite material by reduction of Sb2O3 nanoparticles. We confirmed that similar to 5 nm sized Sb nanoparticles are well distributed onto the rGO sheets, and Sb-rGO composite electrodes showed higher capacity and better cycling performance compared to bare Sb nanoplatelets. This improvement is attributed to increased electrical conductivity owing to incorporation of rGO, which also acts as a buffer against volume expansion of Sb particles during electrochemical reactions. The moderate rate performance of Sb-rGO composite materials was further improved by electrode formulation modification using a carboxymethylcellulose (CMC) binder. An electrode architecture containing Sb-rGO composite material with CMC binder achieved a high capacity (similar to 400 mAh g(-1)) at a high rate (similar to 30 C).