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Indexed by:期刊论文

Date of Publication:2013-12-01

Journal:CHINESE JOURNAL OF CHEMICAL PHYSICS

Included Journals:SCIE、Scopus

Volume:26

Issue:6

Page Number:646-650

ISSN No.:1674-0068

Key Words:Temperature programmed desorption; Time of flight spectrum; Photo-stimulated desorption; Oxygen vacancy

Abstract:We have investigated creation of variable concentrations of defects on TiO2(110)-(1 x 1) surface by 266 nm laser using temperature programmed desorption technique. Oxygen-vacancy defects can be easily induced by ultraviolet light, the defects concentration has a linear dependence on power density higher than 50 mW/cm(2) for 90 s irradiation. No observation of O-2 molecule and Ti atom desorption suggests that UV induced defects creation on TiO2(110)-(1 x 1) is an effective and gentle method. With pre-dosage of thin films of water, the rate of defects creation on TiO2(110)-(1 x 1) is slower at least by two orders of magnitude than bare TiO2(110)-(1 x 1) surface. Further investigations show that water can be more easily desorbed by UV light, and thus desorption of bridging oxygen is depressed.