Designing Highly Efficient CuI Photosensitizers for Photocatalytic H2 Evolution from Water.

A series of CuI photosensitizers was synthesized, characterized, and investigated for photocatalytic H2 evolution from water. A structure-property correlation was established for their catalytic activity and photophysical properties, which was further elaborated by DFT calculations. A new CuI photosensitizer (Cu-TPAPhen) with triphenylamine-substituted phenanthroline ligands showed unprecedentedly high turnover numbers of 19 000 when tested in combination with triethylamine as a sacrificial reagent and colloidal Pt as a H2 evolution catalyst. This work paves the way toward cheap metal-based photosensitizers which can replace noble-metal complexes in photocatalytic systems.