Effect of ultraviolet and x-ray radiation on the work function of TiO2 surfaces

被引：44

作者：

Gutmann, S. ^{[2
]}

Wolak, M. A. ^{[1
]}

Conrad, M. ^{[3
]}

Beerbom, M. M. ^{[1
]}

Schlaf, R. ^{[1
]}

机构：

[1] Univ S Florida, Dept Elect Engn, Tampa, FL 33620 USA

[2] Univ S Florida, Dept Chem, Tampa, FL 33620 USA

[3] Univ S Florida, Dept Mech Engn, Tampa, FL 33620 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2010年 / 107卷 / 10期

基金：

美国国家科学基金会;

关键词：

PHOTOELECTRON-SPECTROSCOPY; PHOTOCATALYTIC OXIDATION; H2O; ADSORPTION; TIO2(110); SOLAR; WATER; DISSOCIATION; INTERFACE; TITANIA;

D O I：

10.1063/1.3410677

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The work functions of nanocrystalline anatase (TiO2) thin films and a rutile single crystal were measured using photoemission spectroscopy (PES). The nanocrystalline titanium dioxide films were deposited in-vacuum using electrospray thin film deposition. A comparison between ultraviolet photoemission spectroscopy (UPS) and low intensity x-ray photoemission spectroscopy (LIXPS) work function measurements on these samples revealed a strong, immediate, and permanent work function reduction (>0.5 eV) caused by the UPS measurements. Furthermore, it was found that regular XPS measurements also reduce the work function after exposure times ranging from seconds to minutes. These effects are similar in magnitude to artifacts seen previously on indium tin oxide (ITO) substrates characterized with XPS and UPS, and are likely related to the formation of a surface dipole through the photochemical hydroxylation of oxygen vacancies present on the TiO2 surface. (C) 2010 American Institute of Physics. [doi:10.1063/1.3410677]

引用

页数：8

共 33 条

[1] Direct comparison of photoemission spectroscopy and in situ Kelvin probe work function measurements on indium tin oxide films [J].