Carbon coated SiO nanoparticles embedded in hierarchical porous N-doped carbon nanosheets for enhanced lithium storage

Abstract

SiO based materials have attracted attention as promising anodes for lithium-ion batteries (LIBs) with high energy density. However, severe volume variation and poor conductivity limit the development of SiO based materials. In this study, carbon coated SiO nanoparticles embedded in N-doped carbon nanosheets (SiO@C/CNSs) have been fabricated through simple ball milling followed by annealing treatment, which is facile and scalable. The g-C₃N₄ precursor plays a multifunctional role as a sacrificial template, nitrogen source for doping, and minor carbon source. The presence of N-doped porous carbon nanosheets could minimize the volume expansion, enhance the reaction kinetics and retain the integrity of the electrode. The SiO@C/CNS anode exhibits a stable reversible capacity of 690 mA h g⁻¹ up to 400 cycles at 1 A g⁻¹ and excellent rate capability. The SiO@C/CNS//LiFePO₄ full cell further confirms its potential as a promising anode for high capacity LIBs.