Molecular Organic Sensitizers for Photoelectrochemical Water Splitting

The photoelectrochemical approach to photoinduced water splitting is gaining increasing interest for solar fuels generation. Dye-sensitized photoelectrochemical cells (DS-PEC) have been studied to improve the collection of the Vis range of solar radiation. Metal complexes have so far been the most investigated dyes but in recent years metal-free organic dyes have emerged as a new frontier for the evolution of the sector. This Minireview systematically describes the use of organic sensitizers and has been organized in terms of dye-sensitized photoactive electrode(s): photoanode; photocathode; tandem DS-PEC with photoanode and photocathode. The main classes of dyes are introduced and described in their key properties, device performance, and water splitting data. Thanks to the increasing number of articles, this review highlights the growing importance of organic sensitizers and their molecular design for a more efficient solar generation of clean fuels.