High-performance flexible SnO2 anode boosted by an N-doped graphite coating layer for lithium-ion and sodium-ion batteries

Abstract

Tin dioxide (SnO2) with multiple electron transport is considered as a potential substitute for graphite due to these advantages of natural abundance, environmental friendliness, and high theoretical capacity. However, the ineluctable volume change and structural crushing limit its practical application. Hence, SnO2 is coated by an N-doped graphite layer to form the flexible composite anode (SnO2@NG), which can provide a conductive network, increase the electronic conductivity, and effectively mitigate the irreversible volume expansion/contraction during the circulation process. Furthermore, the SnO2@NG anode shows a high specific capacity and stable cycle performance in lithium-ion batteries (677.7 mAh g−1 after 100 cycles) and sodium-ion batteries (169.7 mAh g−1 after 100 cycles). This excellent electrochemical performance illustrates that SnO2@NG has broad application prospects for high-performance energy storage systems.