Electrochemical reduction of CO2 on metal carbonyl complexes modified glassy carbon electrodes

Carbon dioxide gas released into the atmosphere in very large amounts every year causes the greenhouse effect and excessive warming of the world and global warming. Therefore, reducing the amount of carbon dioxide is of great importance for the environment. In this thesis, two coordination compounds, [Mn(I)(CO)3(2,2'-bipyridyl)(2-mercaptobenzimidazole)] and [Re(I)(CO)3(2,2'-bipyridyl)(2-mercaptobenzimidazole)] were tested as catalysts for the electrochemical reduction of CO2. Catalytic activity studies were carried out under both homogeneous and heterogeneous catalysis conditions. In the first stage, the electrochemical behavior of the synthesized Mn(I) and Re(I) complex molecules was studied in the absence of CO2 and in the presence of CO2, and thus the catalytic activity of the compounds against CO2 reduction was determined. In the next part of the thesis, firstly the immobilization of Mn(I) and Re(I) complexes on glassy carbon electrode (CKE) was studied. For this purpose, electrochemical immobilization technique was tried and Nafion membrane was used on it. After the stable immobilization of complex molecules on the electrode surface, CO2 reduction studies were carried out using modified electrodes and the obtained CO2 reduction currents were recorded as a measure of catalyst efficiency.