Defective Graphite and Its Decoration with Copper Oxide Nanoparticles Synthesized with Olive Leaf Extract for Electrochemical Water Splitting

Water splitting has been regarded as a promising route to generate hydrogen which is considered as an ideal alternative to fossil fuels due to its light weight, environmentally benign oxidation product and high energy density. For this purpose, solutions of copper oxide or copper–olive leaf extract complexes were synthesized using copper acetate as a precursor and olive leaf extract as a reducer/stabilizer. Highly defected graphite (DG) rods and plates were then decorated with these particles. The decoration process was conducted by simple immersion of the graphitic materials in the solution followed by oxidation at 250 °C to obtain stable cupric oxide nanoparticles on the DGs and used as electrodes. The decorated electrodes were tested for hydrogen evolution reaction (HER) and oxygen evolution reaction in Na2CO3. It was found that the current density and stability for HER reaction can be enhanced as a result of this decoration. The current density variation with temperature variation was monitored and was found to increase when the electrolyte temperature increases from 25 to 48 °C, indicating a possible harvesting of solar thermal energy as assistant in water splitting process.