Designing the efficient and highly stable noble free electrocatalyst for the water electrolysis is great immense for the alternative solution of energy demand. Herein, we report CuO/NiO/rGO nanocomposite for enhanced oxygen evolution reaction via facile co-precipitation method followed by calcination.  By incorporating the CuO and NiO  on rGO sheets results homogeneous tiny nanoparticles morphology dispersed on the graphene sheets which  improving the strong interaction between the metal nanoparticles and carbon based graphene composite. The electrochemical performances of the prepared electrocatalyst were investigated by cyclic voltammetry, linear sweep voltammetry and electrochemical impedance spectroscopy using 1 M alkaline potassium hydroxide (KOH) electrolyte solution. CuO/NiO/rGO nanocomposite achieves low overpotential value of 200 mV at the low current density at 10 mA/cm² and smaller Tafel value of 165 mV/dec. It also exhibits the high electrochemical active surface area value of 132.5 cm² for the CuO/NiO/rGO electrode which provides large number of accessible surface active sites for excellent OER activity. The optimized CuO/NiO/rGO nanocomposite crucially shows low cost inexpensive metal oxides substitution with rGO paves an advantageous way for innovative synergistic approach for the large scale applications.

Keywords: Noble free electrocatalyst, alternative solution, co-precipitation method, synergistic approach, overpotential and oxygen evolution reaction.