CALORIMETRIC ADSORPTION HEATS ON LOW-INDEX NICKEL SURFACES

被引:33
作者
ALSARRAF, N [1 ]
KING, DA [1 ]
机构
[1] UNIV CAMBRIDGE, DEPT CHEM, LENSFIELD RD, CAMBRIDGE CB2 1EW, ENGLAND
关键词
D O I
10.1016/0039-6028(94)90361-1
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
A new method has been devised for detecting the heat evolved when a gas is adsorbed onto a crystal surface. The method forms the basis of an adsorption calorimeter which provides, for the first time, accurate heats of adsorption for adsorbates on metal single crystal surfaces as a detailed function of surface coverage. Coverage-dependent calorimetric heats of adsorption and sticking probabilities for CO on the (111) {100} and {110} planes of nickel have been obtained, enabling comparisons to be made with literature values for isosteric heats. Data for CO adsorption onto nickel surfaces with varying amounts of predosed K have been obtained, demonstrating an unexpectedly large effect of promotion on the heat of adsorption. A model is presented to explain this data. Finally, heats of adsorption for oxygen chemisorption have been obtained for the clean and K predosed nickel surfaces. The data provide a direct measure, of the lateral interaction energies between adatoms. Unexpectedly large values for the pairwise repulsive interaction between 0 adatoms on Ni surfaces have been obtained.
引用
收藏
页码:1 / 7
页数:7
相关论文
共 17 条
  • [1] DIRECT MEASUREMENT OF POTASSIUM-PROMOTED CHANGE IN HEAT OF ADSORPTION OF CO ON NI(100)
    ALSARRAF, N
    STUCKLESS, JT
    KING, DA
    [J]. NATURE, 1992, 360 (6401) : 243 - 245
  • [2] BONZELL HP, 1988, SURF SCI REP, V8
  • [3] AN ULTRAHIGH-VACUUM SINGLE-CRYSTAL ADSORPTION MICROCALORIMETER
    BORRONIBIRD, CE
    KING, DA
    [J]. REVIEW OF SCIENTIFIC INSTRUMENTS, 1991, 62 (09) : 2177 - 2185
  • [4] SINGLE-CRYSTAL ADSORPTION MICROCALORIMETRY
    BORRONIBIRD, CE
    ALSARRAF, N
    ANDERSSON, S
    KING, DA
    [J]. CHEMICAL PHYSICS LETTERS, 1991, 183 (06) : 516 - 520
  • [5] THE CALORIMETRIC DETERMINATION OF THE HEATS OF ADSORPTION OF OXYGEN ON EVAPORATED METAL FILMS
    BRENNAN, D
    HAYWARD, DO
    TRAPNELL, BMW
    [J]. PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1960, 256 (1284): : 81 - 105
  • [6] HOW MANY METAL ATOMS ARE INVOLVED IN DISSOCIATIVE CHEMISORPTION
    BRUNDLE, CR
    BEHM, J
    BARKER, JA
    [J]. JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS, 1984, 2 (02): : 1038 - 1039
  • [7] BURUNDLE CR, 1990, CHEM PHYSICS SOLID A, V3
  • [8] CHRISTENSEN OD, IN PRESS CHEM PHYS L
  • [9] PYROELECTRIC SINGLE-CRYSTAL ADSORPTION MICROCALORIMETRY AT LOW-TEMPERATURES - OXYGEN ON NI(100)
    DIXONWARREN, SJ
    KOVAR, M
    WARTNABY, CE
    KING, DA
    [J]. SURFACE SCIENCE, 1994, 307 : 16 - 22
  • [10] THEORY OF ELECTRONIC-STRUCTURE AND OVERLAYER STRUCTURES OF OXYGEN ON THE NICKEL (001) SURFACE
    GALLAGHER, JM
    HAYDOCK, R
    [J]. SURFACE SCIENCE, 1979, 83 (01) : 117 - 130