Effect of heteroatoms-doped carbon decoration on the cathode surface for sodium-ion batteries

Abstract

Efficient N, S-doped carbon decoration on Na3V2(PO4)3 (NSC@NVP) cathode is, for the first time, successfully prepared using L-cysteine as a single source for heteroatoms-doped carbon in sodium-ion batteries (SIBs). The effect of L-cysteine-derived N, S-doped carbon surface decoration on the electrochemical performance of NSC@NVP is investigated. The findings suggest that the NSC@NVP composite electrode with 5 wt% of L-cysteine (5-NSC@NVP) offers a high specific discharge capacity of 115.8 mAh g−1, which is 98.4% of the theoretical capacity (117.6 mAh g−1) of Na3V2(PO4)3. The 5-NSC@NVP composite electrode with the optimal amount of N, S-doped carbon leads to superior discharge capacity, cycling stability, and rate capability when compared to pristine NVP. The N, S-doped carbon matrix with active sites and defective nature can upgrade the electron and ion conductivities simultaneously while suppressing the agglomeration of NVP particles during cycling, resulting in the enhancement of electrochemical performances with NSC@NVP composites as a cathode material for SIBs.