Facile in situ synthesis of crystalline VOOH-coated VS2 microflowers with superior sodium storage performance

Abstract

The meticulous design of coating structures is an efficient approach for enhancing the cycle life and rate capability of electrode materials. Herein, crystalline VOOH-coated VS₂ microflowers (c-VS₂@VOOH) constructed from nanosheets are successfully prepared by a facile one-step hydrothermal method. The c-VS₂@VOOH composite as a sodium ion battery anode material delivers an excellent cycling stability of 330 mA h g⁻¹ after 150 cycles at 0.2 A g⁻¹. In particular, c-VS₂@VOOH can still afford a high reversible capacity of 356 and 224 mA h g⁻¹ even at 0.5 and 1.0 A g⁻¹, respectively. The high capacity, good stability and enhanced rate capability are mainly attributed to the highly efficient surface sensitization and protection by crystalline VOOH, which can improve sodium ion diffusion and suppress the pulverization of VS₂ nanosheets.