Unraveling the mechanism of catalytic water oxidation via <i>de novo</i> synthesis of reactive intermediate

Artificial photosynthesis has the potential to provide carbon-free fuel. The current systems are limited by the lack of understanding of multi-electron water oxidation catalysts (WOC). Trial and error is the only way that new catalysts are being discovered. A thorough spectroscopic analysis of the prototypical [(tpy)(bpy)Ru(H₂O)]²⁺ -which is the parent complex in the largest family of WOCs- is presented in this study and will give us a clear understanding of dynamics of this catalyst family. This understanding would help to design a catalyst rationally. De novo synthesis of the reactive intermediate with 2,2′-bipyridine-N-oxide, resulted in a hundredfold catalytic activity compare to the parent compound. In situ Raman spectroscopy along with electrolysis of parent and enriched intermediate shed light on the mechanism of the catalysts. Finally, the redox potential of the ligand was shown to be correlated with the rate of O2production.