Quantitative study of F center in high-surface-area anatase titania nanoparticles prepared by MOCVD

The concentration of F center in high-surface-area anatase titania nanoparticles prepared by MOCVD are studied with electron paramagnetic resonance measurements at different time and different temperatures. The results show that the kinetics of F center is dominated by surface process rather than bulk process. With increasing temperature, two temperature dependent regions for the concentration of F center can be clearly identified. The starting temperature and activation energy of the surface process are determined to be 357.4 K and 0.085 eV, respectively. The reaction of F center with oxygen is of zero order and the concentration of F center can be well described by [GRAPHICS] (C) 2004 Elsevier Ltd. All rights reserved.