Coupling Photodriven Multielectron Reduction Of Ruthenium Polypyridyl Complexes With Hydrogen Evolving Co-catalysts

Abstract

With energy demands continuing to increase, the importance of finding a means of converting solar energy into a usable form of chemical energy continues to escalate. Photocatalysis provides a viable approach to harnessing energy from the sun for its use in energy converting reactions such as the water splitting reaction. Ruthenium polypyridyl complexes have played an important role in the growth and advancement of artificial photosynthetic systems, many of which have the ability to utilize solar energy in the process of H2 evolution. This thesis focuses on a biomimetic approach to solar H2 production through multi-electron photocatalysis. The two dinuclear Ruthenium complexes [(phen)2Ru(tatpp)Ru(phen)2]4+ and [(phen)2Ru(tatpq)Ru(phen)2]4+ both have the ability to undergo multiple reductions and store those electrons on the central bridging ligand of each respective complex. These complexes have been investigated as possible photocatalyst and have been found to evolve H2 under the given conditions for extended periods of time. The photocatalytic lifetime of these complexes has been shown to be significantly longer than many of the standard Ruthenium polypridyl photocatalyst.