Nitrogen-Doped porous carbon embedded Sn/SnO nanoparticles as high-performance lithium-ion battery anode

Abstract

Sn-based materials are considered as promising anode for lithium-ion batteries (LIBs) owing to their low operating voltage and high theoretical capacity. Unfortunately, severe volume expansion occurs during cycling resulting in a rapid capacity drop. Herein, a template method is proposed to prepare mixed-phase Sn/SnO embedded nitrogen-doped carbon skeleton (Sn/SnO@NC). The three-dimensional carbon network with superior stability not only prevents the exposure of encapsulated Sn/SnO to the electrolyte but also alleviates the aggregation of Sn/SnO particles and the volume expansion. Furthermore, the introduction of nitrogen provides sites for lithium-ion storage actives and improves the electrical conductivity of the materials. Sn/SnO@NC-4 exhibits high rate capability of 1064 mAh g–1 at 0.1 A g–1 and excellent cycle performance of 631 mAh g–1 at 1.0 A g–1. Moreover, the reversible capacity increases to 859 mAh g–1 after 1000 cycles. This work provides a feasible way to synthesize high-performance Sn-based LIBs anode composites.