Global warming and other adverse environmental effects of fossil fuels have forced humans to consider clean and renewable energy resources. In this context, hydrogen production from water splitting reaction is a key approach. In order to reduce required over potential for water oxidation reaction, it is necessary to use low cost electro catalysts like Ni, Co, Cu, Fe, Mn, and Zn nanostructures. Herein, cobalt nanostructures developed on steel-mesh substrate were applied. Electrochemical method was used for Co nanoflakes growth because of its simplicity and scalability for commercial approach. Surely, the substrate condition is crucial in electro catalysts efficiency. Therefore, using carbonaceous support layers including nanomaterials such as graphene oxide and carbon nanotubes, can reduce over potential and increase efficiency of the electro catalyst. According to the results, 40 wt% of graphene oxide and 60 wt% of carbon nanotubes in the prepared carbon paste led to better growth for cobalt oxide nanoflakes. For the mentioned layer, cobalt was detected in metallic crystalline phase and the overpotential and electrical resistances were measured to be 305 mV and 20 ?, respectively.