Understanding the local structure of a key catalytic reaction intermediate
Scientists from the Fritz Haber Institute in Berlin, together with collaborators from the University of Warwick (UK), have determined the local adsorption site of the methoxy species – the intermediate species of the formaldehyde catalysis reaction. Their findings have been published and selected as an Editor’s Suggestion in the prestigious journal “Physical Review Letters”, August issue.
One of the most studied reactions in surface science is that of methanol oxidation to formaldehyde (H2CO), as it is a building block in the synthesis of many other compounds of specialized and industrial significance. The partial oxidation of methanol (CH3OH) occurs on a Cu(110) surface via an intermediate methoxy species (CH3O). Although this species was recognized over 30 years ago, a detailed understanding of the process on a molecular scale has yet to emerge; thus far the theoretical and experimental interpretations could not be resolved. Now, for the first time, the local adsorption site and associated structure for the methoxy species on the Cu(110) surface has been identified.
The team measured photoelectron diffraction (PhD) spectra at the BESSY synchrotron facility in Berlin. This technique is element and chemical-state specific and can ascertain the nature of the surroundings of each element, i.e., the position of an adsorbed over layer with respect to the underlying substrate. In order to further corroborate their data, the team performed density functional theory calculations. Their resulting model revealed a consistent structural solution that finally reconciled all the previous experimental data. Their report can be found here.
(Published: 18 Aug 2010 |Phys. Rev. Lett. 105, 086101).