Ficus religiosa-mediated CuFe₂O₄: A dual-functional material for supercapacitors and photocatalytic dye degradation

In this work, copper ferrite (CuFe₂O₄) was synthesized for the first time through a green, plant-mediated synthesis methodology using Ficus religiosa leaf extract. In order to investigate the effects of the synthesis conditions, CuFe₂O₄ was synthesized under three conditions, namely, without the addition of additives (CF), with the addition of citric acid (CFC) and with the addition of sodium hydroxide (CFN). Morphological, structural, and optical studies showed the effects of additives on the crystallite size, d-spacing, and bandgap. Electrochemical analysis revealed that CFN provided a capacitance of 54 F/g at 1 A/g, with an energy density of 67 Wh/kg and a power density of 4387 kW/kg, along with good cycling stability of 106% for up to 250 cycles. Photocatalytic-dye degradation experiments showed that CFN sample reduced the malachite green dye by 87.6% in 180 min under visible light irradiation, confirming the dual functional characteristics of the prepared materials. This study identified a viable and economical way to synthesize multifunctional CuFe₂O₄ with potential for use in energy storage and environmental remediation.