Template-Directed Oxidation Synthesis of SnO2 Nanosheets for High-Performance Lithium Storage Application

Tin dioxide (SnO₂) anodes have emerged as a promising and cost-effective alternative for high-energy-density lithium-ion batteries (LIBs). However, their practical implementation is limited by rapid capacity degradation and poor rate performance, which are attributed to severe volume fluctuations, phase aggregation, and sluggish reaction kinetics during cycling. Here, we report a straightforward and efficient template-directed oxidation strategy for the synthesis of two-dimensional polycrystalline SnO₂ nanosheets as advanced LIB anodes using layered tin diselenide nanosheets as sacrificial precursors. The SnO₂ nanosheets synthesized at 500 °C (SnO₂-500) exhibit a wrinkled lamellar architecture comprising interconnected SnO₂ nanoparticles, which is advantageous for applications in LIBs. As a result, the obtained SnO₂-500 anode delivered exceptional cycling stability (623.7 mA h g^–1 after 100 cycles at 0.5 A g^–1), along with outstanding specific capacity and rate performance (1245.7 mA h g^–1 at 0.1 A g^–1 and 554.1 mA h g^–1 at 5 A g^–1).