Laser in-situ synthesis of SnO2/N-doped graphene nanocomposite with enhanced lithium storage properties based on both alloying and insertion reactions

This paper reported a SnO2/N-doped graphene nanocomposite (SnO2/N-Gr) electrode which was prepared by a laser in-situ synthesis method. When demonstrated as anodes for lithium storage, the SnO2/N-Gr electrode showed improved lithium storage capacities and rate performance. In details, a reversible capacity of 830 mAh g(-1) was obtained after 300 cycles at a current density of 300 mA g(-1), and when the current density increased up to 3 A g(-1), the SnO2/N-Gr electrode revealed a high reversible capacity of 600 mAh g(-1). It was proven that the excellent electrochemical performance mainly related to a hybrid lithium storage mechanism which combined with alloying and insertion reactions. By introducing huge numbers of micropores and defects on graphene sheets, N-doping increased the number of hosts for lithium insertion and enhanced the Li+ diffusion rate in graphene sheets, so both of lithium storage capacities and rate performance were effectively improved. The SnO2/N-Gr electrode had a short preparing procedure and good electrochemical performance, which hold potential for development of next generation lithium ion batteries with high specific capacities and good rate performance. (C) 2017 Elsevier B.V. All rights reserved.