Ultrasonically synthesized cadmium ferrite/chromium oxide nanocomposites for high-performance supercapacitors and efficient photocatalytic environmental remediation

The escalating global demand for high-efficiency energy storage and sustainable environmental technologies necessitates the development of advanced multifunctional materials. In this study, cadmium ferrite/chromium oxide nanocomposite (CdFe 2 O 4 /Cr 2 O 3 NCs) was successfully synthesized for the first time via an ultrasonication technique. Structural, morphological, and optical characterizations confirmed the formation of a crystalline cubic phase with an irregular porous architecture, offering the high surface area necessary for optimized catalytic and electrochemical kinetics. The optimized 75% CdFe 2 O 4 /Cr 2 O 3 NC electrode exhibited excellent electrochemical performance. Specifically, it delivered a superior specific capacitance of 1529 F g −1 at 1 mV s −1 as determined by Cyclic Voltammetry and 1283 F g −1 at 1 Ag −1 through galvanostatic charge-discharge measurements. Electrochemical Impedance spectroscopy revealed that 75% CdFe 2 O 4 /Cr 2 O 3 NC possessed a low charge-transfer resistance (0.02602 Ω), outperforming both pristine materials. The asymmetric supercapacitor device delivered a specific capacitance of 312 F g −1 at 1 A g −1 with an energy density of 53.2 Wh kg −1 at a power density of 800 W kg −1 with excellent capacitive retention over 15,000 electrochemical cycles. Furthermore, the material exhibited potent photocatalytic activity, attaining 92.4% degradation efficiency of methylene blue (MB) within 80 min under UV irradiation. These findings highlight the potential of CdFe 2 O₄/Cr 2 O₃ NCs as a cost-effective, synergistic material for innovative energy storage and environmental technologies.