Carboxylic acid induced near-surface restructuring of a magnetite surface

Enthalten in
Communications chemistry 
Volume
2
Issue
1
Article Number
92
Citation
Communications Chemistry 1 (2): 92 (2019-12-01)
Publisher DOI
10.1038/s42004-019-0197-1
Scopus ID
2-s2.0-85071156979
Publisher
Macmillan Publishers Limited, part of Springer Nature
A fundamental knowledge of the interaction of carboxylic acids, such as formic acid, with magnetite surfaces is of prime importance for heterogeneous catalysis and the synthesis of novel materials. Despite this, little is known about the atomic scale adsorption mechanisms. Here we show by in-situ surface X-ray diffraction that the oxygen rich subsurface cation vacancy reconstruction of the clean magnetite (001) surface is lifted by dissociative formic acid adsorption, reestablishing a surface with bulk stoichiometry. Using density functional theory, the bulk terminated, fully formic acid covered surface is calculated to be more stable than the corresponding clean, reconstructed surface. A comparison of calculated and experimental infrared bands supports the bidentate adsorption geometry and a specific adsorption site. Our results pave the way for a fundamental understanding of the bonding mechanism at carboxylic acid/oxide interfaces.
DDC Class
600: Technik