Metal-organic frameworks derived MMoSx (M = Ni, Co and Ni/Co) composites as electrode materials for supercapacitor

Abstract In this present paper, a novel layered multi-metal sulphide was reported as a positive electrode material with abundant electroactive sites and redox reaction centres. Molybdenum and sulfur elements were introduced into the metal-organic frameworks (M-MOF: M = Ni, Co and Ni/Co) to synthesize layered MMoSx by a hydrothermal method. The electrochemical performance comparison of MOFs and six electrode materials demonstrated that NiCoMoSx electrode materials had the best electrochemical performance and the highest specific capacitance. The highest specific capacitance could reach 2595 F g−1 at a current density of 1 A g−1. The NiCoMoSx electrode material also had an excellent cycle stability with a retention rate of 90.8% after 10,000 charge and discharge cycles. In addition, the as-assembled NiCoMoSx//AC assymmetric supercapacitor (ASC) device exhibited a maximum energy density of 48.2 Wh·kg−1 at a power density of 807.2 W kg−1, and the capacity retention rate after 10,000 charge and discharge cycles was 91.6%. This electrochemical performance indicated that this kind of material had a good market development prospect.