Surface reactions of ethanol over UO₂(100) thin film

Journal Article · Thu Oct 08 00:00:00 EDT 2015 · Journal of Physical Chemistry. C

DOI:https://doi.org/10.1021/acs.jpcc.5b08577· OSTI ID:1235892

Mudiyanselage, K. ^[1]; Burrell, A. K. ^[2]; Sadowski, J. T. ^[1]; Idriss, H. ^[3]

---

1. Brookhaven National Lab. (BNL), Upton, NY (United States)
2. Argonne National Lab. (ANL), Argonne, IL (United States)
3. Centre for Research and Innovation (CRI) (Saudi Arabia)

The study of the reactions of oxygenates on well-defined oxide surfaces is important for the fundamental understanding of heterogeneous chemical pathways that are influenced by atomic geometry, electronic structure, and chemical composition. In this work, an ordered uranium oxide thin film surface terminated in the (100) orientation is prepared on a LaAlO₃ substrate and studied for its reactivity with a C-2 oxygenate, ethanol (CH₃CH₂OH). With the use of synchrotron X-ray photoelectron spectroscopy (XPS), we have probed the adsorption and desorption processes observed in the valence band, C 1s, O 1s, and U 4f to investigate the bonding mode, surface composition, electronic structure, and probable chemical changes to the stoichiometric-UO₂(100) [smooth-UO₂(100)] and Ar⁺-sputtered UO₂(100) [rough-UO₂(100)] surfaces. Unlike UO₂(111) single crystal and UO₂ thin film, Ar-ion-sputtering of this UO₂(100) did not result in noticeable reduction of U cations. Upon ethanol adsorption (saturation occurred at 0.5 ML), only the ethoxy (CH₃CH₂O^–) species is formed on smooth-UO₂(100) whereas initially formed ethoxy species are partially oxidized to surface acetate (CH3COO–) on the Ar⁺-sputtered UO₂(100) surface. Furthermore, all ethoxy and acetate species are removed from the surface between 600 and 700 K.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC00112704
• OSTI ID: 1235892
• Report Number(s): BNL-111755-2016-JA; R&D Project: CO009; KC0302010
• Journal Information: Journal of Physical Chemistry. C, Vol. 119, Issue 44; ISSN 1932-7447
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY