Design and optimization of ZnIn₂S₄/Zr₂C@PANI hybrid materials for improved energy storage and hydrogen evolution performance toward advanced energy applications

Enhancing hydrogen evolution efficiency is crucial for advancing next-generation catalysts. This study presents a simple, cost-effective, and environmentally friendly hydrothermal synthesis method for a ZnIn₂S₄/Zr₂C@PANI, designed to enhance energy storage performance for supercapacitor applications. The polyaniline (PANI) combination significantly improves electrical conductivity, electrochemical performance, and stability. ZnIn₂S₄, with its basic layered structure, and 2D Zr₂C MXene, doped with PANI, were comprehensively characterized using XRD, SEM, FTIR, TGA, and BET analyses to crystal structure, morphology, surface area, and particle size. The electrochemical performance was evaluated in a two-electrode system using PVDF binders and conductive fillers, with characterization performed through CV, GCD, and EIS measurements. The ZnIn₂S₄/Zr₂C@PANI showed superior electrochemical performance, resulting in a specific capacity (Q_s) of 2352C/g, capacitance 262.5 F/g, an energy density (E_d) of 64.7 Wh/kg, and power density (P_d) of 1250 W/kg outperforming individual ZnIn₂S₄ and Zr₂C materials. Nyquist plot analysis confirmed the higher conductivity of the PANI-coated composite, which plays a key role in its improved electrochemical efficiency. In this study, combined materials is an applicant for high-performance energy storage devices and hydrogen evolution reaction (HER). The composite can be used in supercapacitors for energy storage and as an efficient catalyst for hydrogen evolution through water splitting.