Nanocrystal–Molecular Hybrids for the Photocatalytic Oxidation of Water

A modular molecular hybrid colloidal photocatalyst composed of TiO₂ nanocrystals (TiO₂-NCs) as a light absorber and the molecular complex [Ru(tda)(pypyr)₂], Ru-tda, as a water oxidation catalyst precursor both anchored onto single-walled carbon nanotubes (SWCNTs) is described. This colloidal molecular hybrid photocatalyst, labeled as Ru-tda/SWCNT/TiO₂-NCs, is a robust material that can be easily prepared and scaled up. At neutral pH, in the presence of 3 sun illumination, the molecular hybrid material Ru-tda/SWCNT/TiO₂-NCs is capable of achieving the photocatalytic oxidation of water to dioxygen in the presence of persulfate, giving an unprecedented turnover number of 229.