Photochemical Water-Splitting with Organomanganese Complexes

Area of Science:

• Inorganic Chemistry
• Photochemistry
• Catalysis

Background:

• Organometallic complexes with water-derived ligands are potential platforms for studying water-splitting reactions.
• The tetrameric complex [Mn(CO)3(μ3-OH)]4 (1) is a key focus due to its structure.

Purpose of the Study:

• To investigate the photochemical water-splitting decomposition of tricarbonyl organomanganese complexes.
• To elucidate the reaction mechanisms and identify products and byproducts.

Main Methods:

• UV irradiation of organomanganese complexes.
• Characterization of organic and manganese-containing side products.
• Isotopic labeling studies using 18O-labeled complex 1.

Main Results:

• Photochemical water-splitting decomposition yields dihydrogen, carbon monoxide, and hydrogen peroxide.
• Labeling studies indicate hydrogen peroxide formation involves free water and dissociation of CO from complex 1.
• Hydrogen production involves protons from hydroxido ligands and other operative processes.

Conclusions:

• The study proposes a mechanism for photochemical water splitting mediated by organomanganese complexes.
• Results provide insights for developing new strategies for water-splitting reactions using organomanganese catalysts.