Electrochemical production of transition metal-based electrocatalysts for water splitting

Due to increasing world population, technological developments and industrial activities, energy resources are decreasing day by day. In particular, the use of non-renewable energy resources (coal, oil, natural gas, etc.) seriously damages the world with effects such as greenhouse gas and global warming. Countries that see these negative effects on the world have started to explore renewable energy sectors in order to ensure the sustainability of energy and humanity in order to leave a prosperous living space for future generations. For this purpose; electrochemical hydrogen production by renewable sources assisted electrolysis may be a viable solution. For this reason, renewable energy sources are very important for the future of the world and also Turkey. Turkey imports many non-renewable energy resources such as oil and natural gas. Unfortunately, imported energy resources seriously affect Turkey's economy. The geographical location of our country is very suitable for renewable energy production, and it is in a very efficient position especially in terms of geothermal, solar and wind energy. We can raise the economy level of our country by investing in renewable energies. In this context, zero carbon emissions, high energy potential and "hydrogen energy", which have recently attracted the attention of researchers, draw attention. Although many methods are used to obtain hydrogen gas, alkaline electrolysis method is preferred due to its advantages. Electrode selection is very important in this method. As it is known, materials containing platinum (Pt) are used as the most efficient electrocatalysts due to the low overvoltages and high current densities of Pt based materials. However, the high cost of Pt greatly restricts its usage. In this study, hydrogen gas was produced by utilizing the electrical energy produced from the wind turbine. During the production, the combination of various electrodes in the anode and cathode positions were observed in the experimental environment and the most convenient electrolysis cell for hydrogen gas production was determined. Platinum (Pt), stainless steel (SS), graphite (G), and copper (Cu) electrodes were used as anodes in the alkaline electrolysis cell. Graphite, was preferred as the cathode electrode due to its high electrical conductivity, low cost and corrosion resistance (in case of power cut). In addition, the G electrode was modified with nickel (Ni), cobalt (Co) and copper (Cu) by galvanostatic method. The ternary coating thickness was approximately 10 µm. The electrode surface was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. The alkaline electrolysis process was carried out with two electrode systems for 15 minutes, the volumes of hydrogen gas (H2(g)) produced for various potentials were determined. According to the experimental results, at each 3 V for 15 minutes of electrolysis time, the produced H2(g) various were; 15 mL; 11.13 mL; 9.30 mL; 8.71 mL; 13.12 mL; 10.10 mL; 10.97 mL for Pt-G (Cell-1), SS-G (Cell-2), G-G (Cell-3), Cu-G (Cell-4), SS-G/NiCoCu (Cell-5), GG/NiCoCu (Cell-6), Cu-G/NiCoCu (Cell-7), respectively.