Ethylene decomposition at undercoordinated sites on Cu(410).
We demonstrate the selective, low-temperature chemistry of ethylene on the strongly undercoordinated sites of Cu(410) by investigating its adsorption by high-resolution electron energy loss spectroscopy (HREELS), X-ray photoelectron spectroscopy (XPS), and temperature-programmed desorption (TPD). After dosing ethylene at approximately 110 K, apart from the expected pi-bonded species adsorbed on terraces, di-sigma-bonded ethylene and carbon are formed at the step edges. The latter product results from the complete dehydrogenation of ethylene and blocks sites for further dissociation and/or di-sigma-adsorption. However, these processes can be restored merely by heating the sample to 900 K, by causing the carbon to diffuse into the bulk. The presented results support the relevance of copper-based catalysts for the steam reforming process.
Kravchuk
Tatyana
T
CNISM and Dipartimento di Fisica, Università di Genova, 16146 Genova, Italy.
Vattuone
Luca
L
Burkholder
Luke
L
Tysoe
Wilfred T
WT
Rocca
Mario
M