The influence of preadsorbed oxygen on the adsorption of CO on two-dimensional Pd islands on a Rh(111)surface

被引：7

作者：

Beutler, A ^{[1
]}

Sandell, A ^{[1
]}

Jaworowski, AJ ^{[1
]}

Wiklund, M ^{[1
]}

Nyholm, R ^{[1
]}

Andersen, JN ^{[1
]}

机构：

[1] Univ Lund, Dept Synchrotron Radiat Res, Inst Phys, S-22100 Lund, Sweden

来源：

SURFACE SCIENCE | 1998年 / 418卷 / 02期

关键词：

carbon monoxide; oxygen; chemisorption; rhodium; palladium; single crystal surfaces; synchrotron radiation photoelectron spectroscopy; adsorption kinetics; surface diffusion;

D O I：

10.1016/S0039-6028(98)00730-4

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 preadsorbed oxygen on the CO adsorption properties of a laterally heterogeneous bimetallic surface consisting of Pd islands on Rh(111) at a Pd coverage of 0.5 monolayers has been studied by high resolution core level photoemission. A surface consisting of clean Pd islands surrounded by oxygen-covered Rh(111) patches was prepared by predosing oxygen at room temperature. By applying core level photoemission to the Pd 3d(5/2) and the C 1s levels, the adsorption of CO on this surface was studied with particular attention being paid to possible CO diffusion between the two surface parts. The CO molecules are found to diffuse from the oxygen-covered Rh(lll) patches onto the Pd islands for low to medium CO exposures. This diffusion direction is opposite of that found previously for the 0.5 ML Pd on Rh(111) system with no oxygen predosing. This reversal of the diffusion direction is argued to be due to a large reduction of the CO adsorption energy on the Rh patches of the surface caused by the preadsorbed oxygen. (C) 1998 Elsevier Science B.V. All rights reserved.

引用

页码：457 / 465

页数：9

共 13 条

[1]

Andersen J. N., 1991, SYNCHROTRON RAD NEWS, V4, P15

[2] Adsorption properties of a mixed surface studied by high resolution core level photoemission: CO 0.5 ML Pd/Rh(111) [J].

Beutler, A ;

Strisland, F ;

Sandell, A ;

Jaworowski, AJ ;

Nyholm, R ;

Wiklund, M ;

Andersen, JN .

SURFACE SCIENCE, 1998, 411 (1-2) :111-122

[3] Coverage- and temperature-dependent site occupancy of carbon monoxide on Rh(111) studied by high-resolution core-level photoemission [J].

Beutler, A ;

Lundgren, E ;

Nyholm, R ;

Andersen, JN ;

Setlik, BJ ;

Heskett, D .

SURFACE SCIENCE, 1998, 396 (1-3) :117-136

[4]

CONRAD H, 1977, SURF SCI, V65, P245, DOI 10.1016/0039-6028(77)90305-3

[5] MANY-ELECTRON SINGULARITY IN X-RAY PHOTOEMISSION AND X-RAY LINE SPECTRA FROM METALS [J].

DONIACH, S ;

SUNJIC, M .

JOURNAL OF PHYSICS PART C SOLID STATE PHYSICS, 1970, 3 (02) :285-&

[6] HYDROGEN AND CO SPILLOVER AT CU/RH(100) BIMETALLIC SURFACES STUDIED BY HIGH-RESOLUTION ELECTRON ENERGY-LOSS SPECTROSCOPY [J].

ESTRADA, CA ;

HE, JW ;

GOODMAN, DW .

JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS, 1992, 10 (04) :2347-2350

[7] ADSORPTION-KINETICS AND ISOTOPIC EQUILIBRATION OF OXYGEN ADSORBED ON THE PD(111) SURFACE [J].

GUO, XC ;

HOFFMAN, A ;

YATES, JT .

JOURNAL OF CHEMICAL PHYSICS, 1989, 90 (10) :5787-5792

[8] AFT-IRAS STUDY OF THE VIBRATIONAL PROPERTIES OF CO ADSORBED ON CU/RU(001) .1. THE STRUCTURAL AND ELECTRONIC-PROPERTIES OF CU [J].

HOFFMANN, FM ;

PAUL, J .

JOURNAL OF CHEMICAL PHYSICS, 1987, 86 (05) :2990-2996

[9]

JAWOROWSKI AJ, IN PRESS

[10] AN IR STUDY OF CO SURFACE-DIFFUSION ON SUBMONOLAYER METAL OVERLAYERS [J].

KUHN, WK ;

HE, JW ;

GOODMAN, DW .

CHEMICAL PHYSICS LETTERS, 1990, 172 (05) :331-334

← 1 2 →