Elucidating the synergistic benefits of the ternary metal components in a cobalt–molybdenum hybrid sulfide–nickel nitride composite as supercapacitor electrodes

Abstract

Inspired by pursuing next-generation supercapacitors through the innovative use of hierarchical multi-component electrodes, we embraced a sophisticated blending strategy. By synergistically integrating diverse classes of materials, we aimed to harness and amplify their unique properties, setting the stage for groundbreaking advancements in energy storage technology. The present study investigates the electrochemical properties of the cobalt–molybdenum-based hybrid sulfide and nickel nitride integrated into one system (CMS/NiN/NF) for application as electrodes in supercapacitors. Integrating nickel nitride into the cobalt–molybdenum hybrid sulfide produced a hierarchical structure, where the nanosheets assemble to form a flower-like structure, which appears to be an interconnected continuous structure analogous to a flower string. Such hierarchical structures enhance the exposure of redox active sites, providing multiple diffusion pathways and acting as an electrolyte reservoir. On evaluating CMS/NiN/NF for its charge storage properties, a specific capacitance value of 4411 F g⁻¹ at a current density of 2 A g⁻¹ was attained, outperforming the hybrid sulfide. Further, when assembled in an asymmetric device with CMS/NiN/NF as the positive electrode and reduced graphene oxide (rGO) as the negative electrode, it exhibits a specific energy value of 58 Wh kg⁻¹ at a specific power of 200 W kg⁻¹. Thus, the blending approach proved rewarding in producing hybrid materials for high-performance energy storage devices.