<p>The development of active bifunctional electrocatalysts is crucial in reducing dependence on precious-metal-based materials for energy production and storage. In this work, we present the synthesis of novel nanocomposites of XCoFe₂O₄ (where X represents Pr or Nd) integrated with graphene oxide (GO) using a hydrothermal method for light-induced hydrogen evolution reaction (HER) and supercapacitor functions. Among the synthesized electrocatalysts, NdPr-CoFe₂O₄/GO exhibits superior HER performance, characterized by a minimal overpotential at photocurrent density of 10 mA cm⁻² in 1 M KOH solution. Additionally, the composite shows a high specific capacitance of 1590.5 F/g at 3 A/g, maintaining approximately 97.6% of its capacitance after 1000 cycles. The enhanced performance is attributed to the synergistic effects of optimal bimetallic substitution, maximized electrochemical surface area, reduced particle size, and minimized charge transfer resistance. This study opens new pathways for the design of spinel ferrite-GO composites for efficient energy conversion and storage applications.</p> Graphical Abstract <p>Graphical abstract presenting applications of synthesized catalysts.</p> <p></p>