Facile synthesis of C, N, P co-doped SiOx as anode material for lithium-ion batteries with excellent rate performance

SiO x has high specific capacity for lithium-ion batteries, but the rate and the cycling performances need to be further improved to satisfy the needs of the future. In this study, the C, N, P doping SiO x /G@CNP anodes are prepared by a facile ball milling and heat treatment process . The electrochemical performances of SiO x are improved by the synergistic effect of C, N, P doping. The SiO x /G@CNP-2 anode with the addition of 20 wt% phytate shows the best electrochemical performances and maintains a specific capacity of 77.45% after 150 cycles at 0.2 A·g −1 . Importantly, it exhibits a remarkable rate performance with specific capacities of 528.2 mAh·g −1 and 370.0 mAh·g −1 even at 3.0 and 5.0 A·g −1 , respectively. Artificial graphite and the carbon shell formed by the thermal decomposition of citric acid contribute to the structural stability of SiO x and improve the cycling performance of the material. Moreover, the addition of P element and high content of pyridine N accelerates the rate of Li + deintercalation, and the conductivity and ion diffusion coefficient of the material are effectively promoted, thus greatly improving the rate performance of the material. This work presented herein provides a simple and feasible method for the preparation of high-performance anode materials.