Confinement sacrifice template synthesis of size controllable heterogeneous double-layer hollow spheres SnO2@Void@HCSs as anode for Li+/Na+ batteries

Abstract

Based on the confinement Sacrifice Template Synthesis strategy, we constructed and synthesized the size controllable heterogeneous double-layer hollow spheres SnO 2 @Void@HCSs, which exhibit high specific capacity and good cycling stability as an anode material in Li + /Na + batteries. • We used a confinement sacrifice template synthesis strategy to successfully synthesize of heterogeneous double-layer hollow spheres SnO 2 @Void@HCSs. • We use two different strategies of regulation to control the size of the internal SnO 2 hollow spheres of SnO 2 @Void@HCSs. • The heterostructure double-layer hollow spheres further enhances structural electrochemical performance of SnO 2 @Void@HCSs. Because of its large theoretical capacity and low potential, tin oxide (SnO 2 ) has a promising future in lithium ion batteries (LIBs) and sodium ion batteries (SIBs). However, the slow reaction kinetics and structural instability inherent in the cell cycling process limit its rate and cycle capabilities. We designed a double-layer hollow spheres structure (SnO 2 @Void@HCSs) to overcome these problems. Notably, size controllable hollow SnO 2 spheres were confined growth in uniformly sized hollow carbon spheres to fabricate the double-layer hollow spheres structure with nanometer void by the method of hydrothermal sacrificial template. The double-layer hollow spheres structure not only successfully reduced SnO 2 volume expansion, but also afforded an abundance of active sites with a high specific surface area to promote alkali metal ion transport. When SnO 2 @Void@HCSs was used as anode materials, the discharge capacities of LIBs and SIBs after 500 cycles were 749.2 mAh/g and 335.6 mAh/g at 1 A/g, respectively. The outstanding electrochemical performance revealed that the structure exhibited a broad application prospect for energy storage and provided a reference for the rational design of heterostructure double-layer hollow spheres.