Recent trends and challenges in heteroatom-rich carbon-based cathode for Zn-Ion hybrid supercapacitors

Abstract

The quest for environmentally friendly and highly effective energy storage solutions has raised awareness of heteroatom-rich carbon materials as potential active cathodes for zinc-ion hybrid supercapacitors (ZIHSC). These substances offer a distinctive combination of elevated electrical conductivity, large surface area, and abundant electroactive sites because of the addition of heteroatoms like phosphorus, sulfur, and nitrogen. Doping with heteroatoms improves the hydrophilicity of the carbon material, enhancing the electrolyte accessibility and ion transport. Magnified cycling stability of ZIHSC is observed due to the strong bonding between heteroatoms and carbon, which can mitigate the structural degradation during repeated charge–discharge cycles. Heteroatom-rich carbon-based cathodes for ZIHSCs face challenges such as maintaining structural stability and preventing heteroatom leaching during repeated charge–discharge cycles, which can degrade performance. To address these challenges, researchers are developing advanced synthesis methods to achieve uniform doping and enhance structural stability, while also exploring protective coatings and binder materials to prevent heteroatom leaching and improve electrode–electrolyte interface stability. This review explains the latest progress, highlights the ongoing challenges, and provides insights into future research directions for heteroatom-rich carbon materials in hybrid supercapacitor applications.