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 SnO 2 content and structure of SnO 2 /TiO 2 multishell microspheres (SnO 2 /TiO 2 -MMs). Especially, the redundant SnO 2 could be automatically removed from the TiO 2 framework when the molar percentage of Sn to Ti reaches to 80.5%, resulting in that the element percentage and structure of SnO 2 /TiO 2 -MMs could be simultaneous optimized. Through optimizing, the reversible discharge capacity and cycle life of SnO 2 /TiO 2 -MMs can be significantly improved in lithium ion batteries. The reversible discharge capacity of SnO 2 /TiO 2 -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.