Abstract
Sodium ion batteries (SIBs) have recently made a comeback as a favourable form of energy storage. Previously, the development of sodium based batteries waned due to the performance inferiority compared to lithium-based batteries1. However, immense demands of electrical energy storage systems have brought SIBs back into the spotlight due to their ample material supply and economical costs2. Hence, investigations are well underway to enhance the electrochemical performance of SIBs and its subcomponents. In this work, three distinct ZnIn2S4 samples were synthesized into anode active materials for SIBs. Each individual sample had unique modifications to their crystal structure, particle morphology and material mixtures. The anodes were fabricated into half-cells and evaluated through galvanostatic cycling. Excellent electrochemical performances were recorded, exhibiting long cycling retention rates (90% after 2500 cycles @ 2A/g), high specific capacity (628mAh/g @ 2A/g) and ultrahigh rate performance (389mAh/g @ 100A/g). Material analysis techniques such as XRD and SEM revealed the exemplary performances can be attributed to the increase in unit cell volume and specific surface area. CV and EIS investigations were also conducted, validating the half-cell testing data. This work unveils a high performance anode material for SIBs and a potential modification strategy for alternative electrode materials.