Strain Dependent Light-off Temperature in Catalysis Revealed by Planar Laser-Induced Fluorescence

• Understanding how specific atom sites on metal surfaces lower the energy barrier for chemical reactions is vital in catalysis. Studies on simplified model systems have shown that atoms arranged as steps on the surface play an important role in catalytic reactions, but a direct comparison of how the light-off temperature is affected by the atom orientation on the step has not yet been possible due to methodological constraints. Here we report in situ spatially resolved measurements of the CO2 production over a cylindrical-shaped Pd catalyst and show that the light-off temperature at different parts of the crystal depends on the step orientation of the two types of steps (named A and B). Our finding is supported by density functional theory calculations, revealing that the steps, in contrast to what has been previously reported in the literature, are not directly involved in the reaction onset but have the role of releasing stress.

Ämnesord

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Nyckelord

sites

reactivity

density functional theory

noble

steps

crystal

carbon-monoxide

cylindrical crystal

ates of america

p917

metal-surfaces

v108

platinum

stepped surfaces

planar laser-induced fluorescence

CO oxidation

Chemistry

CO oxidation

cylindrical crystal

density functional theory

planar laser-induced fluorescence

steps

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)