Characteristics of nanoparticles of mixed Cu–Zn–Mg spinel ferrites: A study of structural and electrochemical attributes

Abstract

Spinel ferrites have some benefits when used as supercapacitor electrode materials, most notably their outstanding long-term cycle stability and energy storage capacity. The materials we investigated were prepared and included Cu doping into Zn–Mg ferrites; these materials are designated as Zn0.4Mg0.5Cu0.1Fe2O4 (ZCM1), Zn0.3Mg0.5Cu0.2Fe2O4 (ZCM2), and Zn0.2Mg0.5Cu0.3Fe2O4 (ZCM3). A variety of techniques, such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) analyses, electron paramagnetic resonance (EPR), and various electrochemical methods, were used to conduct a thorough analysis of their structural features, surface morphology, chemical composition, electrochemical activity, and capacitive performance. We used the solvothermal reflux synthesis method to dope the Zn–Mg ferrites with Cu to improve their performance. The ZCM3 electrode was the result of this change, and it showed a best specific capacitance (Cs) of 508.25 F/g at a current density (CD) of 1.75 A/g. Interestingly, this particular capacitance was higher than the other electrode materials such as ZCM1 and ZCM2 that we examined in this research.