Cobalt(II) and Copper(II) based Molecular Catalysts for Hydrogen Production

Hydrogen takes special attention as the most promising fuel for the future use in transportation and energy storing in terms of sustainability, C-Neutrality and energy conversion. Solar-driven water splitting for hydrogen production represents one fascinating pathway for clean energy conversion and energy storage from visible light irradiation into chemical bonds. The transition metal complexes especially first row transition (3d) metals like iron, manganese, cobalt, nickel and copper based molecular complexes are capable to catalyze the reduction of protons into molecular hydrogen at low over potential or using light energy sources. We are interested to develop robust cobalt and copper based catalyst that could preserve their molecular nature under photo and electrocatalytic conditions. This thesis describes the development of different ligands with different substituents which will help to compare the reactivity as well as redox potential of complexes for water reduction. Here, we successfully designed and synthesized four different types of tridentate ligands (L1, L2, L3, L4). We successfully synthesized Co(II) complexes M1 and M2 with ligands L3 and L4 respectively. The binuclear Cu(II) complex M3 synthesized by using L4. All the ligands and metal complexes were characterized by various spectroscopic tools. The molecular structure of the metal complexes confirmed by single crystal X-ray crystallography which would be robust catalysts for hydrogen evolution