Research output: Contribution to Journal/Magazine › Journal article › peer-review
Formation, atomic distribution and mixing energy in two-dimensional PdxAg1-x surface alloys on Pd(111). / Engstfeld, A. K.; Hoster, H. E.; Behm, R. J.
In: Physical Chemistry Chemical Physics, Vol. 14, No. 30, 14.08.2012, p. 10754-10761.Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Formation, atomic distribution and mixing energy in two-dimensional PdxAg1-x surface alloys on Pd(111)
AU - Engstfeld, A. K.
AU - Hoster, H. E.
AU - Behm, R. J.
PY - 2012/8/14
Y1 - 2012/8/14
N2 - The formation and atom distribution in two-dimensional PdxAg1-x/Pd(111) monolayer surface alloys were studied by high resolution scanning tunnelling microscopy (STM) with chemical contrast. From short-range order (SRO) parameters, we calculate preferences for like or unlike nearest neighbours to elucidate the mixing behaviour of the two components for various sub monolayer Ag surface contents. In the regime of low Ag surface contents (60% Ag) result in a disperse distribution of the atoms in the surface. Effective pair interactions (EPIs) were derived by comparing the measured distribution with distributions obtained using Monte Carlo (MC) simulations. From the EPIs, we derived a function for the mixing energy, which can describe the change from clustering to a disperse distribution. The effects of the resulting surface atom distributions and of the Ag coverage dependent surface mixing/demixing on catalytic reactions are discussed.
AB - The formation and atom distribution in two-dimensional PdxAg1-x/Pd(111) monolayer surface alloys were studied by high resolution scanning tunnelling microscopy (STM) with chemical contrast. From short-range order (SRO) parameters, we calculate preferences for like or unlike nearest neighbours to elucidate the mixing behaviour of the two components for various sub monolayer Ag surface contents. In the regime of low Ag surface contents (60% Ag) result in a disperse distribution of the atoms in the surface. Effective pair interactions (EPIs) were derived by comparing the measured distribution with distributions obtained using Monte Carlo (MC) simulations. From the EPIs, we derived a function for the mixing energy, which can describe the change from clustering to a disperse distribution. The effects of the resulting surface atom distributions and of the Ag coverage dependent surface mixing/demixing on catalytic reactions are discussed.
KW - SCANNING-TUNNELING-MICROSCOPY
KW - SHORT-RANGE ORDER
KW - PD-AG CATALYST
KW - CO ADSORPTION
KW - SELECTIVE HYDROGENATION
KW - ETHYLENE HYDROGENATION
KW - PDAG/PD(111) SURFACE
KW - BIMETALLIC SURFACES
KW - METAL-SURFACES
KW - ACETYLENE
U2 - 10.1039/c2cp41104k
DO - 10.1039/c2cp41104k
M3 - Journal article
VL - 14
SP - 10754
EP - 10761
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
SN - 1463-9076
IS - 30
ER -