In silico study of reaction mechanisms and design principles for water oxidation catalysts

Abstract

Throughout the last decades the water oxidation process has been extensively investigated. However, open questions remain on the reaction mechanism and the possible intermediates in the catalytic cycle. Indeed, different catalysts can function through different reaction routes. Some of them work in a proton-coupled electron transfer (PCET) pathway, while other catalysts have a non-PCET behaviour. Some of these problems lie in the very short lifetime of intermediates, which makes it difficult to characterize them experimentally. Within this context, DFT calculations represent a very useful tool. In fact quantum-mechanical computational tools allow exploring and analyzing the possible intermediates and study and compare different reaction pathways in order to find the energetically most likely one. In the same way the thermodynamics of the catalytic cycle and the kinetics of the reaction coordinates can be analyzed. The specific aim of this thesis is the study of different catalysts and reaction pathways to find clues about the mechanism of the reaction and develop guiding principles for the design of efficient water oxidation complexes