Auto-adjustment of structure and SnO2 content of SnO2/TiO2 microspheres for lithium-ion batteries

Abstract

The optimization strategies of nanoarchitectures with rational composition are important for improving the properties of composites, but which are complicated and challenging. Herein, we demonstrate a facile optimization method for auto-adjusting the SnO2 content and structure of SnO2/TiO2 multishell microspheres (SnO2/TiO2-MMs). Especially, the redundant SnO2 could be automatically removed from the TiO2 framework when the molar percentage of Sn to Ti reaches to 80.5%, resulting in that the element percentage and structure of SnO2/TiO2-MMs could be simultaneous optimized. Through optimizing, the reversible discharge capacity and cycle life of SnO2/TiO2-MMs can be significantly improved in lithium ion batteries. The reversible discharge capacity of SnO2/TiO2-MMs delivers the 1045 mAh g−1 after 650 cycles at the current rate of 0.1 A g−1. Even at the current rate of 0.2 A g−1, the capacity of 591 mAh g−1 can also be delivered after 2000 cycles. This may provide a new strategy or optimized method for building the rational multishell nanoarchitectures of composites.