Highly conductive triple-layered hollow MnO2@SnO2@NHCS nanospheres with excellent lithium storage capacity for high performance lithium-ion batteries

Abstract

Tin based nanomaterials revealed large application potential for lithium storage. Multilayered hollow MnO₂@SnO₂@NHCS nanospheres made up of the SnO₂@NHCS inner layer and the MnO₂ external layer (MnO₂ nanosheets) were constructed through a facile hydrothermal method followed by an in situ reduction reaction. The hierarchical structure can effectively buffer volume changes, prevent aggregation of active materials and enhance electronic conductivity. As anode materials of lithium-ion batteries, the as-obtained MnO₂@SnO₂@NHCS-5 composite exhibited high reversible capacities of 1053.8 mA h g⁻¹ after 100 cycles at 100 mA g⁻¹ and an outstanding cycling stability (349.7 mA h g⁻¹ after 1000 cycles at 5000 mA g⁻¹). The best electrochemical performance was ascribed to the introduction of the nitrogen element and the construction of a rigid hollow structure, which obviously enhanced the migration rate of electrons and provided enough space for volume expansion. The design of a novel hollow multilayered structure and its excellent electrochemical performances may offer inspiration for its extensive utilization in lithium-ion batteries.