Nitrogen-doped carbon-encapsulated SnO2–SnS/graphene sheets with improved anodic performance in lithium ion batteries

Abstract

A dual-doping approach for nitrogen-doped carbon-coated SnO₂–SnS/graphene nanosheets (N–C@SnO₂–SnS/GN) has been developed, using hydrothermal carbonization of sucrose with SnO₂-decorated graphene and ammonium thiocyanate and a subsequent thermal treatment. The resulting hybrid manifests a typical two-dimensional core–shell architecture, with a N-doped carbon coating over the SnS- and SnO₂-decorated graphene nanosheets. Used as the anode material in lithium ion batteries (LIBs), N–C@SnO₂–SnS/GN delivers a high specific capacity of 1236 mA h g⁻¹ at a current density of 0.1 A g⁻¹ after 110 cycles, which outperforms most state-of-the-art tin-based LIB anodes with core–shell structures.