Review and Outlook of Zinc Sulfide Nanostructures for Supercapacitors

Abstract

Supercapacitors have increased considerable interest due to their unique characteristics such as extended life cycle, high-power density, and environmental friendliness. They serve as a bridge for the energy-power difference between a traditional capacitor and batteries/fuel cells. Selection of the ideal electrode material for a particular application is a critical parameter that affects the efficiency of supercapacitor devices. Transition-metal sulfides exhibit multiple oxidation states and display outstanding supercapacitance performance. Metal sulfides are comparatively superior than metal oxides because of their better conductivity, higher electrochemical activity, and eminent thermal and mechanical stability. A comprehensive summary of the zinc sulfide (ZnS)-based nanomaterials as supercapacitor electrodes is on view. With a band gap of 3.5–3.8 eV, ZnS is one of the first discovered II–VI semiconductors. ZnS has been revealed as a sustainable and promising supercapacitance electrode material owing to its facile synthesis and magnificent electrochemical performance. This review has covered the recent research and development of ZnS nanostructures for supercapacitor electrodes. Additionally, synthesis of ZnS nanostructures and influencing parameters, selection of composite materials, and their design have been summarized for highly efficient supercapacitor devices. As far as our knowledge, this review is the first holistic description of ZnS-based supercapacitor electrodes and devices from basics to recent advancements.