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

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 MMoS x by a hydrothermal method. The electrochemical performance comparison of MOFs and six electrode materials demonstrated that NiCoMoS x 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 NiCoMoS x 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 NiCoMoS x //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. • Six kinds of materials were synthesized by hydrothermal method to make working electrodes, and electrochemical properties were tested and compared. • It is proved that cobalt-nickel composite has higher specific capacitance and better electrochemical performance after molybdenum-doped vulcanization with MOF as precursor. • NiCoMoS x electrode material has good electrochemical properties and excellent cycling stability. • The assembled asymmetric supercapacitor has good energy storage and can light up red LED. [ABSTRACT FROM AUTHOR]