Photoreactions of Organic Compounds with TiO2 Single Crystal Surfaces

摘要: In this work the photoreactions of two organic molecules: acetic acid and ethanol, over rutile TiO2(110), TiO2(011) (011) reconstructed surface TiO2(001) single crystals are presented. Comparison with corresponding dark reaction is also given. The steady state at 320 K {011}-faceted under UV irradiation indicated formation methane, ethane CO2. These expected products so-called “Photo-Kolbe” acid. While methane was not sensitive to addition molecular oxygen could be carried out in UHV conditions catalytically that required continual gas phase for its photo-catalytic production occur. quantum yield computed equal 0.05, while depletion layer width barrier height were found 18 nm 0.18 eV, respectively. photoreaction ethanol conducted TiO2(110) that, oxidation ethoxides acetate species occurs within investigated pressure range (10−6–10−9 torr). absence (base 2 × 10−10 torr) or presence hydrogen a up 10−6 torr negligible photo-reaction occurred. Fitting observed decay upon Langmuir-type analysis, as function oxygen, binding constant later ca. 107 torr−1. This value, together initial coverage ethoxide 0.5 respect Ti atoms, may indicate number adsorbed needed maximum rate similar free atoms.