THE ELECTRONIC-STRUCTURE OF CEO2 THIN-FILMS - THE INFLUENCE OF RH SURFACE DOPANTS

被引：49

作者：

PFAU, A

SCHIERBAUM, KD

GOPEL, W

机构：

[1] Institute of Physical and Theoretical Chemistry, University of Tübingen, D-72076 Tübingen

来源：

SURFACE SCIENCE | 1995年 / 331卷

关键词：

CERIUM OXIDE; ELECTRON ENERGY LOSS SPECTROSCOPY; POLYCRYSTALLINE SURFACES; RHODIUM; SURFACE ELECTRONIC PHENOMENA; VISIBLE AND ULTRAVIOLET PHOTOELECTRON SPECTROSCOPY; X-RAY PHOTOELECTRON SPECTROSCOPY;

D O I：

10.1016/0039-6028(95)00272-3

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The influence of Rh surface doping on the electronic structure of stoichiometric CeO2 surfaces is studied using detection-angle dependent XPS, UPS and HREELS. Ph surface doping leads to an increase of the Ce3+ concentration localized at the surface as shown by the Ce 3d core level emissions. Upon deposition of Ph in the submonolayer range UPS shows Rh 4d associated states to develop between the oxide O 2p band and the Fermi level E(F). These states broaden with increasing coverage towards E(F), and finally metallic Rh is formed. Besides the typical loss structure of undoped, stoichiometric CeO2 an additional transition is observed in the HREELS spectra of Rh doped CeO2 at 1.6 eV loss energy stoichiometric CeO which is interpreted as a charge transfer transition from Ph 4d derived states to empty Ce 4f states. For coverages below 1.5 monolayers Rh is found to reduce the work function of clean, stoichiometric CeO2 from 4.69 eV to a minimum value of 4.35 eV at a coverage of 0.5 monolayers.

引用

页码：1479 / 1485

页数：7

共 19 条

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