SnO2 nanoparticles confined in a graphene framework for advanced anode materials

Abstract

SnO2 nanoparticles (SNPs) entrapped in a graphene framework are synthesized for use as an anode material in Li ion batteries. A framework is prepared by covalently linking SNPs-anchored graphene oxide layers with diboronic acids. The framework provides the SNPs with more effective buffering than thermally reduced graphene oxide. SNPs in a graphene framework maintain the initial particle size and morphology after repeated charge-discharge cycles, with no inter-particle aggregation. The volume increase of the composite, accompanied by Li+ insertion into SNPs, is also significantly suppressed. The isolation of an individual nanoparticle and the firmness of a framework, which are ascribed to densely cross-linked graphene layers, results in better cyclability and rate performance by comparison with thermally reduced SNPs-anchored graphene oxide.