Synthesis of SnS2 Ultrathin Nanosheets as Anode Materials for Potassium Ion Batteries

Potassium(K) ion batteries present their promising application for large-scale energy storage systems with cost-effective characteristic. Unfortunately, the large K ion radius results in sluggish K ion diffusion kinetics and volume expansion of the electrode during the K ion insertion/extraction process. It is a challenge to explore capable anode materials with remarkable K ion storage ability. Herein, we design and prepare SnS2 ultrathin nanosheets via a facile hydrothermal process. When severing as anode materials for K ion batteries with optimized electrolyte, SnS2 presents an improved capacity and rate ability. The capable electrochemical performance is ascribed to the reduced ion diffusion pathway and capacitor-dominated K-ion storage process. In addition, the K ion storage mechanism of SnS2 is investigated by the ex-situ X-ray diffraction technique.