Proton-Coupled Electron Transfer in Natural and Artificial Photosynthesis

Proton-Coupled Electron Transfer in Natural and Artificial Photosynthesis 

The remarkable system used by nature to convert sunlight into more useful energy equivalents is the source of inspiration for artificial photosynthesis - the development of synthetic systems that mimic the natural photosynthetic processes of light-driven water splitting and CO2 reduction, for the production of solar fuels.  

The major bottleneck towards the achievement of efficient artificial photosynthesis is the difficulty in matching the solar irradiance flux with rates of kinetically complex multielectron reactions, which, as seen in Nature, requires 

Proton-Coupfed Electron Transfer A Carrefour of Chemical Reactivity Traditions 

Proton-coupled electron transfer (PCET) is a ubiquitous process in biology and chemistry and plays an essential role in multi-electron, multi-proton transfer processes of biological relevance, such as photosynthesis and respira-tion. The coupling between proton and electron motions stabilizes reaction intermediates, by preventing charge build-up during the accumulation of redox equivalents. The key role of PCET natural photosynthesis is probably the major contributor to this effect. 

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