Synergistic Integration of FeCo₂S₄ Particles with Holey Graphene Hydrogel for Enhanced Performance Solid-state Supercapacitor

Abstract

In this study, the holey graphene was prepared by microwave-assisted chemical etching. The three-dimensional (3D) holey graphene hydrogel was obtained through hydrothermal self-assembly method, followed by the introduction of FeCo₂S₄ particles. The resulting holey graphene hydrogel, characterized by high specific surface area and abundant pores combined with FeCo₂S₄ with high pseudocapacitance by interfacial interaction, shortened the mass transport path and enhanced the specific capacitance. The findings reveal that the holey graphene hydrogel/FeCo₂S₄ (FeCo₂S₄/HGH) composite exhibits high specific capacitance and impressive rate capability (413.4 F·g⁻¹ at 1 A·g⁻¹, 300.4 F·g⁻¹ at 6 A·g⁻¹). The symmetric supercapacitor operated within a stable potential window of 0.1–1.6 V, achieving specific capacitance of 127.5 F·g⁻¹ at 1 A·g⁻¹, and can deliver 37.1 Wh·kg⁻¹ at a power density of 1 499 W·kg⁻¹. Besides, under the current density of 3 A·g⁻¹, the supercapacitor retained 90.8% of its capacitance after 5 000 cycles, demonstrating exceptional cycle stability. This study presents an efficient method for fabricating advanced integrated supercapacitors electrodes with enhanced energy density.

Keywords

holey graphene / FeCo₂S₄/HGH / microwave assisted chemical etching / symmetric supercapacitor

RIGHTS & PERMISSIONS

Wuhan University of Technology and Springer-Verlag GmbH Germany, Part of Springer Nature