Nickel-molybdenum bimetallic sulfide decorated biomass derived carbon support for high performance asymmetric supercapacitor application

Biomass - derived carbon electrode material with a porous structure is widely used in supercapacitor applications, which can improve electron transfer and shorter ion diffusion pathways. In this work, the garlic peel biomass carbon (GPBC), NiMo₃S₄(NMS) and garlic peel biomass carbon decorated with NiMo₃S₄ (GPBC/NMS) composite were prepared through a in situ two-step hydrothermal method. The synthesized materials were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), energy dispersive x-ray spectroscopy (EDS), Transmission electron microscopy techniques (TEM), Raman spectroscopy and Brunauer-Emmett-Teller (BET) techniques were used to analyze the structure, morphology and specific surface areas and X-ray photoelectron spectroscopy (XPS). The prepared bimetallic metal sulfide on a biomass - derived carbon namely the GPBC/NMS composite is used in supercapacitor application. The GPBC/NMS composite electrode exhibits good cycle performance with high specific capacity of 304C/g at current density of 1 A/g in a 3 M KOH electrolyte solution. The electrochemical performance of the GPBC/NMS//GPBC asymmetric supercapacitor device produces an excellent energy density 45.5 Wh kg⁻¹ at a power density of 1125 W kg⁻¹ in the 1.6 V operating potential window. The GPBC/NMS//GPBC also exhibits 93 % retention of its initial capacitance after the 10,000 GCD cycle performance. The above results demonstrate a new way of developing high performance electrode materials for energy storage applications.