Self-supporting 1T-MoS2@WS2@CC composite materials for potential high-capacity sodium storage system

Abstract

Pure phase MoS2 has low conductivity, but with high theoretical specific capacity, and WS2 possesses a high intrinsic conductivity, but suffer from rapid capacity fading. Predictably, the combination of these two transition metal sulfide compounds can complement each other and improve electrochemical performance comprehensively. Whereas, bimetallic phase sulfide of MoS2 and WS2 composites have not been researched in SIBs. In this paper, 1T metallic phase MoS2 and WS2 vertically growth on flexible carbon cloth (CC) surface (1T-MoS2@WS2@CC) by a simple hydrothermal method. The electrochemical performance was improved by heterojunction synergistic effect and the enhanced interlayers of the composite material. Specifically, the superelevation reversible capacity of 529.4 mAh/g can be obtained even after 100 cycles at the current density of 100 mA g−1, and the 259.2 mAh/g capacity can be maintained even at high current density of 1000 mA g−1 after 60 cycles. Besides, the designed 1T-MoS2@WS2@CC composite material has excellent rate performance and cycle stability which are guarantee for battery core performance. Thus, there is every reason to believe that the advanced 1T-MoS2@WS2@CC electrode material has great potential in the future high performance energy storage devices.