Publication 910

Nat. Commun., 11, 3499, 2020 DOI:10.1038/s41467-020-17125-4
Photocathode functionalized with a molecular cobalt catalyst for selective carbon dioxide reduction in water

Université de Nantes, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
Université de Paris, Laboratoire d’Electrochimie Moléculaire LEM, CNRS, F-75013 Paris, France
Université de Nantes, CNRS, Institut des Matériaux Jean Rouxel, IMN, F-44000 Nantes, France
Institut Universitaire de France (IUF), F-75005 Paris, France

Artificial photosynthesis is a vibrant field of research aiming at converting abundant, low energy molecules such as water, nitrogen or carbon dioxide into fuels or useful chemicals by means of solar energy input. Photo-electrochemical reduction of carbon dioxide is an appealing strategy, aiming at reducing the greenhouse gas into valuable products such as carbon monoxide at low or without bias voltage. Yet, in such configuration, there is no catalytic system able to produce carbon monoxide selectively in aqueous media with high activity, and using earth-abundant molecular catalyst. Upon associating a p-type Cu(In,Ga)Se2 semi-conductor with cobalt quaterpyridine complex, we herein report a photocathode complying with the aforementioned requirements. Pure carbon dioxide dissolved in aqueous solution (pH 6.8) is converted to carbon monoxide under visible light illumination with partial current density above 3 mA cm−2 and 97% selectivity, showing good stability over time.