Molecular and heterogeneous water oxidation catalysts: recent progress and joint perspectives

The development of reliable water oxidation catalysts (WOCs) is essential for implementing artificial photosynthesis on a large technological scale. WOC research has evolved into two major branches, namely molecular and heterogeneous catalysts. Manifold design principles and plenty of mechanistic insights have been developed in these individual fields after decades of investigations. Over the past years, a growing need for knowledge transfer between both sides has emerged in order to expedite the development and optimization of next-generation WOCs. In this review, we first provide selected recent highlights in the area of molecular WOCs with different nuclearities, together with current mechanistic insight. WOCs offering molecular integrity under operational conditions are ideal platforms for elucidating reaction mechanisms and well-defined structure-function correlations at the atomic level. Next, recent mechanistic advances and design strategies for heterogeneous WOCs are illustrated for representative examples, together with a discussion of their inherent limitations in mechanistic studies. Finally, illustrative cases of knowledge transfer between molecular and heterogeneous WOCs are discussed to highlight the advantages of combining the best of both catalyst types. For the sake of conciseness, this review focuses primarily on WOCs based on the first-row transition metals, which are attracting increasing attention for both fundamental studies and economic applications.

Automated summary

The text emphasizes the importance of reliable water oxidation catalysts (WOCs) for artificial photosynthesis on a large scale. It discusses the evolution of WOC research into molecular and heterogeneous branches, as well as the growing need for knowledge transfer between these two fields. The review highlights recent developments in both molecular and heterogeneous WOCs, focusing on design principles, mechanistic insights, and the benefits of combining the best of both catalyst types.