Abstract
Photocatalytic hydrogen production was first detected in a high vacuum condition for platinum-loaded nanocrystalline anatase-titanium dioxide (TiO2) thin films, using a newly developed monitoring system with a quadrupole mass spectrometer. In the presence of methanol of 10-6 Torr, partial pressures of hydrogen (H2) and formaldehyde (HCHO), generated due to the decomposition of methanol, were observed clearly to change simultaneously with the UV irradiation onto the TiO2 films. Photolysis of gas-phase water was also detected, thus revealing that this new method is capable to evaluate sensitively such the photocatalytic activities in high vacuum at a real-time scale.