Innovative Nanoarchitectures: CuO:Er₂O₃ Synergy for Enhanced Performance in Energy Storage and Generation Applications

ABSTRACT In this study, we have synthesized facile Cu‐based CuO:Er 2 O 3 nanoelectrode material for energy storage and generation. CuO:Er 2 O 3 nanomaterial was synthesized employing phyto‐extract of Amaranthus viridis L. (AVL) as stabilizing and reducing agents. Spherical‐shaped CuO:Er 2 O 3 nanomaterial was initially employed to study supercapacitor behavior. The specific capacitance of 82.25 F/g was found at 0.5 A/g by galvanostatic charge–discharge, whereas the value of 319 F/g was achieved at 2 mV/s by cyclic voltammetry (CV) measurements. Furthermore, CuO:Er 2 O 3 electrode was investigated for water splitting energy generation potential and revealed an overpotential value of 323 mV at 10 mA/cm 2 for hydrogen evolution reaction (HER). However, for the oxygen evolution reaction (OER), an overpotential value of 370 mV was found. The electrochemical impedance analysis revealed the faster flow of electrons and ions, suggesting great conductivity and lower resistance of the fabricated electrode. Thus, current electrochemical results are proposing CuO:Er 2 O 3 as an competent electrode for overall energy‐generating as well as storage applications.