Sustainable hybrid supercapacitors based on CoFe2O4-C composite

Abstract

The need for efficient energy storage systems has promoted the development of supercapacitors. Researchers have recently focused on building hybrid supercapacitors and synthesizing electrode materials using ecological and easily scalable methods. This work presents the development of hybrid supercapacitors based on cobalt ferrite-carbon composite. The spinel ferrite was synthesized by co-precipitation followed by heat treatment, and a ferrite-glucose precursor was used to obtain a mesoporous composite with a specific surface area of 41.195 m²·g⁻¹. Adding carbon does not structurally modify the cobalt ferrite but significantly improves the electrochemical properties. The electrochemical characterization in a three-electrode cell yielded a maximum specific capacitance of 548.1 F·g⁻¹ at a current density of 14.5 A·g⁻¹. The composite was mixed with sustainable activated carbon in different proportions to assemble solid-state hybrid supercapacitors. A maximum specific capacitance and energy of 69.8 F·g⁻¹ and 27.9 Wh·kg⁻¹ were obtained with a symmetric 1.2 V device, corresponding to a specific power of 94 W·kg⁻¹. These results show that it can develop hybrid supercapacitors based on the CoFe₂O₄-C composite, synthesized by a simple, low-cost, and environmentally friendly method.