Rational Design of an Electron-Reservoir PtII Complex for Efficient Photocatalytic Hydrogen Production from Water

Herein we report a Pt-II complex containing a 4,4-bis[4-(triphenylsilyl)phenyl]-2,2-bipyridine ligand as a molecular catalyst for water splitting. Systematic studies of the electrochemical and electronic properties of this catalyst, in comparison with two control complexes, reveal electron-reservoir characteristics upon two-electron reduction. A turnover number of 510000 was recorded by employing this complex as a water reduction catalyst in combination with a state-of-the-art photosensitizer and N,N-dimethylaniline as a sacrificial electron donor, which represents a large improvement over the control complexes that do not contain the tetraphenylsilyl ligand substitution.