Photostimulated adsorption and desorption of oxygen on sno2 and tio2: Some new experimental data and a phenomenological model

Abstract

We have measured the photoeffect on the oxygen adsorbed on SnO2 and TiO2 under different surface treatments and pressures in the range 10-4 to 10-1 Torr, with particular attention to the photoeffect inversion. In TiO2 at room temperature the photoeffect inversion pressure is found to be about 10-3 Torr, the photoadsorption and photodesorption occuring above and below this pressure, respectively. This inversion is interpreted as to be related to the transition from a gas- adsorbate equilibrium situation to a non-equilibrium situation, due to the pinch-off mechanism. In agreement with our interpretation, we found relation. © 1974 The Japan Society of Applied Physics.