Mesoporous graphene/carbon framework embedded with SnO2 nanoparticles as a high-performance anode for lithium storage
The huge volume variation and poor electronic conductivity of tin oxide (SnO2) during the discharge/charge process greatly limit its practical application in lithium ion batteries (LIBs). Hybridization with graphene is a widely-used method to improve its electrochemical performance, but it still faces some limitations. In this work, we integrate carbon encapsulation with graphene hybridization to synthesize a sandwich-like carbon-coated SnO2/graphene composite via a flexible method. In this case, a mesoporous graphene/carbon framework (MCF) derived from acid etching of an as-prepared graphene@Fe3O4@C composite was used as a robust matrix for the embedment of SnO2. When evaluated as an anode material for LIBs, the resultant MCF@SnO2 composite exhibits a high second reversible capacity of 1205 mA h g−1 at 0.2 A g−1, excellent cycling performance with 668 mA h g−1 capacity retention after 200 cycles at 1.0 A g−1, and a good rate capability. This facile strategy could be further extended to embed other metal oxide nanoparticles into the mesoporous carbon framework for applications in energy conversion and storage.