Sustainable Mechanochemical Fabrication of NiFe2O4@rGO Conductive Hybrid for Energy Storage and Environmental Remediation

This study reports a green, mechanochemical one-pot synthesis of a nickel ferrite/reduced graphene oxide (NiFe₂O₄@rGO) hybrid designed for dual applications in energy storage and environmental remediation. The integration of NiFe₂O₄ nanoparticles with rGO forms a conductive nano-network that significantly enhances charge transport and interfacial redox activity. In a three-electrode configuration using 4.0 M NaOH electrolyte, the NiFe₂O₄@rGO hybrid delivers a high specific capacitance of 496 F g⁻¹ at a current density of 1 A g⁻¹, markedly outperforming pristine NiFe₂O₄. A symmetric supercapacitor assembled from the hybrid exhibits a specific capacitance of ~103 F g⁻¹ at 1 A g⁻¹ with an excellent cycling stability, retaining 93.16% of its initial capacitance after 5000 charge–discharge cycles. In addition, the NiFe₂O₄@rGO hybrid demonstrates outstanding photocatalytic activity, achieving over 99% degradation of rhodamine B dye within 60 min under UV irradiation, along with high reusability and structural stability. The enhanced electrochemical and photocatalytic performances are attributed to the synergistic interaction between NiFe₂O₄ and rGO, which promotes efficient electron transport and active site utilization. This work presents a scalable, eco-friendly synthesis strategy for a multifunctional hybrid material capable of bridging high-performance supercapacitor technology and wastewater treatment applications.