Formation of multilayer-Eosin Y-sensitized TiO2 via Fe3+ coupling for efficient visible-light photocatalytic hydrogen evolution

Anefficient visible-light active photocatalyst ofmultilayer-Eosin Y-sensitized TiO2 is prepared through linkage of Fe3þ between not only TiO2 and EosinYbut also different EosinYmolecules to form three-dimensional polymeric dye structure. The multilayer-dye-sensitized photocatalyst is found to have high light harvesting efficiency and photocatalytic activity for hydrogen evolution under visible light irradiation (l> 420 nm). On the optimum conditions (1:1 initial molar ratio of Eosin Y to Fe(NO3)3, initial 10 10 3 M Eosin Y, and 1.0 wt% Pt deposited by in situ photoreduction), its maximal apparent quantum yield for hydrogen evolution is 19.1% from aqueous triethanolamine solution (TEOA aq). The present study highlights linking between dye molecules via metal ions as a general way to develop efficient visible-light photocatalyst.