Interlayer expansion of few-layered Mo-doped SnS2 nanosheets grown on carbon cloth with excellent lithium storage performance for lithium ion batteries

Abstract

New conceptions of developing various nanostructure materials supported on conductive substrates are urgently required for additive-free integrated electrodes for lithium ion batteries (LIBs). In this work, Mo-doped SnS₂-based nanosheets were directly grown on a conductive substrate, carbon cloth, via a facile hydrothermal method. Significantly, the as-synthesized samples possess a three-dimensional network structure consisting of interconnected nanosheets, which can be directly employed as additive-free integrated electrodes for LIBs. The as-obtained CC@Sn_0.9Mo_0.1S₂ nanosheets exhibit initial high discharge and charge capacities of 2033.6 and 1869.8 mA h g⁻¹ at a current density of 1 A g⁻¹, with a coulombic efficiency of 91.9%. A high reversible discharge capacity of 1950.8 mA h g⁻¹ is obtained after 200 cycles. Moreover, a high reversible capacity of 914.5 mA h g⁻¹ is achieved even at a high current density of 5 A g⁻¹, which significantly exceeds the theoretical capacity of commercial graphite and reversible capacity of SnS₂. A full lithium ion battery was assembled composed of the CC@Sn_0.9Mo_0.1S₂ anode and a commercial LiCoO₂ cathode, which also delivered high capacity and cycling stability. The excellent electrochemical lithium storage performance of Mo-doped SnS₂ could be attributed to the molybdenum doping, which limited the number of layers of the nanosheets, enlarged the interlayer spacing and generated rich defects.