DYNAMIC STUDIES OF SURFACE-REACTIONS WITH MICROSCOPIC TECHNIQUES

被引:37
作者
BLOCK, JH [1 ]
EHSASI, M [1 ]
GORODETSKII, V [1 ]
机构
[1] RUSSIA ACAD SCI, BORESKOV INST CATALYSIS, NOVOSIBIRSK, RUSSIA
关键词
D O I
10.1016/0079-6816(93)90067-6
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
Work function changes which are combined with surface processes can be investigated and used to characterize adsorption states during heterogeneous catalytic reactions. The oscillatory behaviour of the CO-oxidation was studied on palladium and platinum single crystal surfaces as well as on platinum field emitter tips. On macroscopic crystals the reaction was simultaneously characterized by mass spectrometric analysis and by work function measurements via a Kelvin probe with an area of almost-equal-to 30 mm2 being probed. In a second series of experiments photoelectron emission microscopy (PEEM) was applied to follow surface processes with a spatial resolution of almost-equal-to 1 mum. Finally, Pt surfaces were investigated with a lateral resolution of almost-equal-to 20 angstrom by using field emission microscopy (FEM). Gas phase coupling of oscillations as demonstrated by the simultaneous oscillations of two separated macroscopic crystals, was missing at small areas of a field emitter. The PEEM registers local oscillations under conditions where the Kelvin probe fails to register dynamic processes. FEM-data showed that critical radii for nucleation could be as small as few angstrom.
引用
收藏
页码:143 / 168
页数:26
相关论文
共 28 条
  • [1] REACTION FRONTS AND PULSES IN THE CO OXIDATION ON PT - THEORETICAL-ANALYSIS
    BAR, M
    FALCKE, M
    ZULICKE, C
    ENGEL, H
    EISWIRTH, M
    ERTL, G
    [J]. SURFACE SCIENCE, 1992, 269 : 471 - 475
  • [2] STABLE STATIONARY STATES OF COUPLED CHEMICAL OSCILLATORS - EXPERIMENTAL-EVIDENCE
    BARELI, K
    REUVENI, S
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1985, 89 (08) : 1329 - 1330
  • [3] BLOCK JH, 1992, IN PRESS 10TH P INT
  • [4] EHSASI M, 1989, SURF SCI, V210, pL198, DOI 10.1016/0039-6028(89)90593-1
  • [5] REACTION-RATE OSCILLATION OF CO OXIDATION ON PT(210)
    EHSASI, M
    REZAIESEREJ, S
    BLOCK, JH
    CHRISTMANN, K
    [J]. JOURNAL OF CHEMICAL PHYSICS, 1990, 92 (12) : 7596 - 7609
  • [6] Ehsasi M., 1989, Journal of Chemical Physics, V91, P4949, DOI 10.1063/1.456736
  • [7] COUPLED CHEMICAL OSCILLATORS IN CATALYTIC-OXIDATION OF CO ON PD(110) SURFACES
    EHSASI, M
    FRANK, O
    BLOCK, JH
    CHRISTMANN, K
    [J]. CHEMICAL PHYSICS LETTERS, 1990, 165 (2-3) : 115 - 119
  • [8] EHSASI M, IN PRESS ULTRAMICROS
  • [9] EHSASI M, IN PRESS J CHEM PHYS
  • [10] KINETIC OSCILLATIONS IN THE CATALYTIC CO OXIDATION ON A PT(110) SURFACE
    EISWIRTH, M
    ERTL, G
    [J]. SURFACE SCIENCE, 1986, 177 (01) : 90 - 100