Investigation of Co-, Ni-, and Cu-based ferrite/g-C3N4 composites for superior supercapacitor performance

Abstract This study focus on the synthesis and electrochemical characterization of spinel ferrite and C 3 N 4 composite materials for energy storage applications. Spinel ferrites such as NiFe 2 O 4 , CuFe 2 O 4 , and CoFe 2 O 4 were synthesized and combined with C 3 N 4 to improve their performance in supercapacitor applications. The synthesis process involved coating 1 mg of electrode slurry onto nickel foam to exploit its porous structure, which enhances active material retention. Electrochemical measurements revealed that at a current density of 1 A/g, NiFe 2 O 4 exhibited a capacitance value of 238.09 F/g, while the NiFe 2 O 4 /C 3 N 4 composite reached 847.61 F/g, demonstrating superior capacitance retention and good cycling stability. Similarly, CuFe 2 O 4 and CuFe 2 O 4 /C 3 N 4 composites were characterized, achieving a capacitance of 424.7 F/g and maintaining 92.8% efficiency over 10,000 cycles. CoFe 2 O 4 and CoFe 2 O 4 /C 3 N 4 composites displayed even higher performance, with a capacitance of 2291.03 F/g at 1 A/g. The combination of high surface area C 3 N 4 with ferrites enhances active material loading, ion–electron interactions, and charge transfer, leading to improved electrochemical performance. These materials, derived from abundant, non-toxic elements, offer an environmentally friendly, cost-effective solution for energy storage, reducing environmental impact while enhancing performance.