Tuning the efficiency of CoFe2O4@rGO composite by encapsulating Ag nanoparticles for the photocatalytic degradation of methyl violet dye and energy storage systems

Abstract

In the present work, a silver nanoparticle-encapsulated CoFe₂O₄@reduced graphene oxide composite (Ag NPs/CoFe₂O₄@rGO) was prepared via a simple chemical co-precipitation technique. The formation of the materials was confirmed by various physico-chemical tools, and the composite was tested for photocatalytic and energy storage applications. Ag NPs/CoFe₂O₄@rGO composite demonstrated remarkable plasmonic photocatalytic activity in the degradation (96%) of aqueous solution of methyl violet dye under visible light irradiation. Further, the electrochemical properties of the as-fabricated Ag NPs/CoFe₂O₄@rGO composite Ni foil electrode were elucidated by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) tests and electrochemical impedance spectroscopy (EIS) in 1 M aqueous KOH electrolyte. Noticeably, Ag NPs/CoFe₂O₄@rGO composite electrode exhibited a specific capacitance of 970 F g⁻¹ at a scan rate of 5 mV s⁻¹ with excellent cycling stability (93% retention after 3000 cycles at 2 A g⁻¹). The favorable performance demonstrated the synergistic effect of CoFe₂O₄ and Ag NPs with improved surface area, rendered through rGO in the composite, thus indicating that the material is promising and efficient for photocatalysis and energy storage devices.