Water adsorption on the Fe3O4(111) surface: dissociation and network formation. Issue 23 (5th June 2018)

• Record Type: Journal Article
• Authors: Zaki, Eman; Mirabella, Francesca; Ivars-Barceló, Francisco; Seifert, Jan; Carey, Spencer; Shaikhutdinov, Shamil; Freund, Hans-Joachim; Li, Xiaoke; Paier, Joachim; Sauer, Joachim
• Is Part Of: Physical chemistry chemical physics. Volume 20:Issue 23(2018)
• Page Start: 15764
• Page End: 15774
• Publication Date: 2018-06-05
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c8cp02333f
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Water adsorption on Fe3 O4 (111) is studied in detail using infrared spectroscopy, temperature programmed desorption, micro-calorimetry and density functional theory. Abstract : We monitored adsorption of water on a well-defined Fe3 O4 (111) film surface at different temperatures as a function of coverage using infrared reflection–absorption spectroscopy, temperature programmed desorption, and single crystal adsorption calorimetry. Additionally, density functional theory was employed using a Fe3 O4 (111)-(2 × 2) slab model to generate 15 energy minimum structures for various coverages. Corresponding vibrational properties of the adsorbed water species were also computed. The results show that water molecules readily dissociate on regular surface Fetet1 –O ion pairs to form "monomers", i.e., terminal Fe–OH and surface OH groups. Further water molecules adsorb on the hydroxyl covered surface non-dissociatively and form "dimers" and larger oligomers, which ultimately assemble into an ordered (2 × 2) hydrogen-bonded network structure with increasing coverage prior to the formation of a solid water film.