Facile synthesis of rGO/DyMnO3 nanocomposite directly grown on nickel foam for supercapacitor applications

Abstract

The advancement of innovative energy storage electrode materials requires the immediate growth of redox-active and sensible design of multifunctional electrochemical active materials. Supercapacitors are increasingly favored for the storage of energy owing to their large specific power, rapid charge/discharge times, and long-term durability. The potential electrochemical energy storage using metal oxides motivated our research team to create DyMnO₃ and their hybrid with reduced graphene oxide (rGO), via hydrothermal process in rGO/DyMnO₃, as an electrocatalyst with comparatively high electrical conductivity and appropriate electrochemical active surface. This research was conducted utilizing a 2 M KOH as electrolyte within a possible window between −0.1 and 0.6 V. Impressively, our synthesized sample exhibited the remarkable specific capacitance of 1536.78 F g⁻¹ on current density of 1 A g⁻¹, attributed to quick charge storage and delayed discharging mechanism. The addition of rGO to porous spherical DyMnO₃ enhances electrochemical performance, providing a specific surface area of 250 m² g⁻¹ and an electroactive surface area of 2675 cm⁻². The created device displayed electrochemical activity with a high energy density of 149.40 Wh kg⁻¹ at a power density of 719.86 W kg⁻¹, respectively. Oxygen vacancy enhances results, indicating the rGO/DyMnO₃ nanocomposite's potential for SCs and other electrochemical applications.