<p>Researchers are working on innovative strategies to overcome the threats of environmental deterioration and energy crisis. In this regards, rare earth metal-based nanocomposites are under concern due to their excellent electrochemical performance. In this study, Sm₂O₃/NiFe₂O₄ based nanocomposite was prepared via sol-gel approach for the assessment of Supercapacitor and water splitting applications. The prepared nanocomposites were characterized with distinct techniques, like Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDX). The XRD confirmed the formation of Sm₂O₃/NiFe₂O₄ crystal system. However, SEM depicted a hybrid integrated uniform structure with improved surface morphology while transmission electron microscope demonstrated well dispersed hybrid morphology. The Sm₂O₃/NiFe₂O₄ nanocomposite demonstrated an specific capacitance and energy density of 1975.4 F/g and 68.5 Wh/kg, respectively at 5 mV/s. Furthermore, hydrogen evolution reaction of prepared nanocomposite material showed lower over potential value 209 mV at 10 mA cm^–2. Similarly, the Sm₂O₃/NiFe₂O₄ depicted the Tafel slope of 107 mV/decade better than pure electrode material.</p> Graphical Abstract <p></p>