Enhanced capacitive performance of a Ag-functionalized low crystalline Co3O4/graphene composite

Abstract

In this paper, a Ag–Co₃O₄/graphene aerogel (GA) composite was prepared by dispersing Ag-modified low crystalline Co₃O₄ nanowires onto a GA carrier. The capacitive performance of the Ag–Co₃O₄/GA was studied and the results were compared with those of Co₃O₄/GA. Ag-functionalized Co₃O₄/graphene with precursor n(Ag)/n(Co) = 0.51 exhibited the highest specific capacitance (C_s) value of 1180 F g⁻¹ at a current density of 1 A g⁻¹, and the capacity retention was 86% after 1000 cycles at 5 A g⁻¹. Furthermore, the electrochemical impedance spectroscopic results revealed a certain effect of electrolyte ions on the supercapacitive behavior. Ag-functionalized Co₃O₄/GA is believed to be one of the potential materials for supercapacitors with high performance.