General preparation of metal organic frameworks derived heterogeneous NiS2/Ni3S4 nanomaterials for high-performance hybrid supercapacitor

Recently, the development of transition metal sulfides as electrode materials in supercapacitors has been hindered by their slow reaction kinetics and insufficient stability. In this paper, a heterogeneous NiS 2 /Ni 3 S 4 composite of a small size was generated via a solvothermal process using Ni-MOF as a precursor. The heterogeneous NiS 2 /Ni 3 S 4 is conducive to the increase of redox sites and optimization of ion diffusion channels. Meanwhile, the small size of NiS 2 /Ni 3 S 4 improves the redox reaction kinetics between the electrochemically active material and electrolyte. These advantages resulted in S-Ni-MOF(1) with a high specific capacitance of 895.56 F g −1 (403.00 C g −1 ) at 0.5 A g −1 , as well as features of battery-type materials. In addition, a bamboo-derived active carbon (BBC) was prepared for the hybrid supercapacitor device (S-Ni-MOF(1)//BBC). The device possessed the largest energy density of 50.92 Wh kg − ¹ at the power density of 1,500 W kg −1 . After 10,000 charge/discharge processes, its specific capacitance reached 74.47% of its initial value. The connected devices supported the illumination of LEDs, demonstrating good application prospects. This work will offer novel references for designing heterogeneous sulfide and MOF derived nanomaterials.