Heteroatom Doping Combined with Microstructured Carbon to Enhance the Performance of Sodium-Ion Batteries

A simple and effective procedure for the synthesis of nitrogen (N) and sulfur (S) co-doped carbon accompanied by the formation of favorable microstructure is developed. The synthesized N and S co-doped carbon materials are thoroughly investigated by electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, and nitrogen adsorption measurements. When applied as anodes in sodium-ion batteries, high sodium storage capacities and excellent cyclic stability are obtained. It is observed that the contents of N and S atoms and the microstructure of the carbon have a significant effect on the performance of sodium-ion battery. Under optimized synthetic conditions, the N and S co-doped carbon materials have a specific capacity of 287.2mAhg(-1) in the second cycle and a stable specific capacity of 232.6mAhg(-1) even after 500cycles at 0.5Ag(-1). Moreover, the simple and facile procedure can be conventionally adopted for the preparation of other heteroatom-doped carbon materials.