Direct Visualization of Catalytically Active Sites at the FeO-Pt(111) Interface

Autor: Lindsay R. Merte, Helene Zeuthen, Yunhai Bai, Guowen Peng, Wilhelmine Kudernatsch, Lutz Lammich, Manos Mavrikakis, Flemming Besenbacher, Stefan Wendt
Jazyk: angličtina
Rok vydání: 2015
Předmět:
Zdroj: Kudernatsch, W, Peng, G, Zeuthen, H, Bai, Y, Merte, R L, Lammich, L, Besenbacher, F, Mavrikakis, M & Wendt, S 2015, ' Direct Visualization of Catalytically Active Sites at the FeO-Pt(111) Interface ', ACS Nano, vol. 9, no. 8, pp. 7804-7814 . https://doi.org/10.1021/acsnano.5b02339
DOI: 10.1021/acsnano.5b02339
Popis: Within the area of surface science, one of the "holy grails" is to directly visualize a chemical reaction at the atomic scale. Whereas this goal has been reached by high-resolution scanning tunneling microscopy (STM) in a number of cases for reactions occurring at flat surfaces, such a direct view is often inhibited for reaction occurring at steps and interfaces. Here we have studied the CO oxidation reaction at the interface between ultrathin FeO islands and a Pt(111) support by in situ STM and density functional theory (DFT) calculations. Time-lapsed STM imaging on this inverse model catalyst in O2 and CO environments revealed catalytic activity occurring at the FeO-Pt(111) interface and directly showed that the Fe-edges host the catalytically most active sites for the CO oxidation reaction. This is an important result since previous evidence for the catalytic activity of the FeO-Pt(111) interface is essentially based on averaging techniques in conjunction with DFT calculations. The presented STM results are in accord with DFT+U calculations, in which we compare possible CO oxidation pathways on oxidized Fe-edges and O-edges. We found that the CO oxidation reaction is more favorable on the oxidized Fe-edges, both thermodynamically and kinetically.
Databáze: OpenAIRE