Selectivity of hydrogen chemisorption on clean and lead modified palladium particles; a TPD and photoemission study

Z. Paál, G. Loose, G. Weinberg, M. Rebholz, R. SchlÖgl

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

This work describes hydrogen chemisorption on clean and lead modified palladium particles obtained from decomposition of PdO. TPD is used as a chemical probe to test the surface properties of several states of metallic palladium relevant in practical selective hydrogenation catalysts. These states differ in oxygen content and the presence of a lead modifier. XPS and UPS data serve as a basis for identifying the surface properties. TPD spectra show a very broad low temperature peak-likely bulk hydride decomposition-and a sharp TPD peak between 330 and 380 K. This latter can be devided into three rather poorly separated subpeaks; addition of Pb does not shift peak maxima but decreases the central subpeak and eliminates the high temperature peak completely. This points to the interaction of Pb with specific surface sites rather than to bulk alloy formation. The enhancement of selectivity in hydrogenation obtained from lead modification is considered as a geometric site blocking effect rather than to arise from a bulk modification of the valence electronic structure of palladium metal.

Original languageEnglish
Pages (from-to)301-315
Number of pages15
JournalCatalysis Letters
Volume6
Issue number3-6
DOIs
Publication statusPublished - May 1990

Fingerprint

Palladium
Photoemission
Temperature programmed desorption
Chemisorption
chemisorption
palladium
Hydrogen
photoelectric emission
selectivity
Hydrogenation
Surface properties
hydrogen
Lead
surface properties
hydrogenation
Decomposition
decomposition
Hydrides
Electronic structure
X ray photoelectron spectroscopy

Keywords

  • decomposition of PdO
  • Head as surface modifier
  • hydrogen chemisorption
  • Palladium
  • TPD
  • UPS
  • XPS

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Catalysis

Cite this

Selectivity of hydrogen chemisorption on clean and lead modified palladium particles; a TPD and photoemission study. / Paál, Z.; Loose, G.; Weinberg, G.; Rebholz, M.; SchlÖgl, R.

In: Catalysis Letters, Vol. 6, No. 3-6, 05.1990, p. 301-315.

Research output: Contribution to journalArticle

Paál, Z. ; Loose, G. ; Weinberg, G. ; Rebholz, M. ; SchlÖgl, R. / Selectivity of hydrogen chemisorption on clean and lead modified palladium particles; a TPD and photoemission study. In: Catalysis Letters. 1990 ; Vol. 6, No. 3-6. pp. 301-315.
@article{3c0b33fd25ee4d7b9406849c582d63cb,
title = "Selectivity of hydrogen chemisorption on clean and lead modified palladium particles; a TPD and photoemission study",
abstract = "This work describes hydrogen chemisorption on clean and lead modified palladium particles obtained from decomposition of PdO. TPD is used as a chemical probe to test the surface properties of several states of metallic palladium relevant in practical selective hydrogenation catalysts. These states differ in oxygen content and the presence of a lead modifier. XPS and UPS data serve as a basis for identifying the surface properties. TPD spectra show a very broad low temperature peak-likely bulk hydride decomposition-and a sharp TPD peak between 330 and 380 K. This latter can be devided into three rather poorly separated subpeaks; addition of Pb does not shift peak maxima but decreases the central subpeak and eliminates the high temperature peak completely. This points to the interaction of Pb with specific surface sites rather than to bulk alloy formation. The enhancement of selectivity in hydrogenation obtained from lead modification is considered as a geometric site blocking effect rather than to arise from a bulk modification of the valence electronic structure of palladium metal.",
keywords = "decomposition of PdO, Head as surface modifier, hydrogen chemisorption, Palladium, TPD, UPS, XPS",
author = "Z. Pa{\'a}l and G. Loose and G. Weinberg and M. Rebholz and R. Schl{\"O}gl",
year = "1990",
month = "5",
doi = "10.1007/BF00763996",
language = "English",
volume = "6",
pages = "301--315",
journal = "Catalysis Letters",
issn = "1011-372X",
publisher = "Springer Netherlands",
number = "3-6",

}

TY - JOUR

T1 - Selectivity of hydrogen chemisorption on clean and lead modified palladium particles; a TPD and photoemission study

AU - Paál, Z.

AU - Loose, G.

AU - Weinberg, G.

AU - Rebholz, M.

AU - SchlÖgl, R.

PY - 1990/5

Y1 - 1990/5

N2 - This work describes hydrogen chemisorption on clean and lead modified palladium particles obtained from decomposition of PdO. TPD is used as a chemical probe to test the surface properties of several states of metallic palladium relevant in practical selective hydrogenation catalysts. These states differ in oxygen content and the presence of a lead modifier. XPS and UPS data serve as a basis for identifying the surface properties. TPD spectra show a very broad low temperature peak-likely bulk hydride decomposition-and a sharp TPD peak between 330 and 380 K. This latter can be devided into three rather poorly separated subpeaks; addition of Pb does not shift peak maxima but decreases the central subpeak and eliminates the high temperature peak completely. This points to the interaction of Pb with specific surface sites rather than to bulk alloy formation. The enhancement of selectivity in hydrogenation obtained from lead modification is considered as a geometric site blocking effect rather than to arise from a bulk modification of the valence electronic structure of palladium metal.

AB - This work describes hydrogen chemisorption on clean and lead modified palladium particles obtained from decomposition of PdO. TPD is used as a chemical probe to test the surface properties of several states of metallic palladium relevant in practical selective hydrogenation catalysts. These states differ in oxygen content and the presence of a lead modifier. XPS and UPS data serve as a basis for identifying the surface properties. TPD spectra show a very broad low temperature peak-likely bulk hydride decomposition-and a sharp TPD peak between 330 and 380 K. This latter can be devided into three rather poorly separated subpeaks; addition of Pb does not shift peak maxima but decreases the central subpeak and eliminates the high temperature peak completely. This points to the interaction of Pb with specific surface sites rather than to bulk alloy formation. The enhancement of selectivity in hydrogenation obtained from lead modification is considered as a geometric site blocking effect rather than to arise from a bulk modification of the valence electronic structure of palladium metal.

KW - decomposition of PdO

KW - Head as surface modifier

KW - hydrogen chemisorption

KW - Palladium

KW - TPD

KW - UPS

KW - XPS

UR - http://www.scopus.com/inward/record.url?scp=0009602612&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0009602612&partnerID=8YFLogxK

U2 - 10.1007/BF00763996

DO - 10.1007/BF00763996

M3 - Article

VL - 6

SP - 301

EP - 315

JO - Catalysis Letters

JF - Catalysis Letters

SN - 1011-372X

IS - 3-6

ER -