Molecular electrochemical water photo-oxidation

SARA N. MOYA BETANCOURT; JULIETA S. RIVA; ASTRID OLAYA; GIRAULT, HUBERT H.

Mar del Plata

Congreso; 34th Topical Meeting of the International Society of Electrochemistry; 2023

International Society of Electrochemistry

Towards the goal of artificial photosynthesis, water photo-oxidation remains a major challenge. Light-driven water oxidation on semiconductor photoelectrodes has been the major pole of investigations with slow progress due to the difficulty in developing electrode materials with high chemical stability, suitable optoelectronic properties, and high catalytic efficiencies. The molecular routes have relied on the synthesis of organometallic compounds acting as antennae and redox catalysts, but none have yet found industrial applications.Here, we shall present our based on the self-assembly of simple organic molecules such as tetrathiafulvalene (TTF) and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (TCNQF4). In the former case, we shall show that TTF+TTF assemblies on carbon electrodes can act as antennae and redox electron acceptors for the 4-electron oxidation. In the latter case, the assembly of TCNQF4 also performs the photo-oxidation of water but at water-butyronitrile interface.In both cases, a water-butyronitrile emulsion is used where the aqueous phase “pumps” the protons formed during water oxidation and where the organic phase is used to dissolve the different molecular assemblies.The extension of this work to batch water-splitting in emulsion systems will be presented.