Methanol adsorption and dissociation on LaMnO₃ and Sr doped LaMnO₃ (001) surfaces

Journal Article · 20 June 2017 · Surface Science

DOI: https://doi.org/10.1016/j.susc.2017.06.010 · OSTI ID:1432170

Beste, Ariana ^[1]

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1. Univ. of Tennessee, Knoxville, TN (United States). Joint Inst. for Computational Sciences; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Using density functional theory, we investigate in this paper methanol adsorption and dissociation on the MnO₂- and LaO-terminated LaMnO₃ (001) surface as a function of Sr dopant enrichment in and near the surface. In response to bulk cleavage, we find electron depletion of the negatively charged MnO₂ surface layer that is enhanced by Sr doping in the subsurface. In contrast, we observe electron accumulation in the positively charged LaO surface layer that is reduced by Sr doping in the surface layer. Methanol adsorbs dissociatively on the LaO termination of the LaMnO₃ (001) surface. Methanol adsorption on the LaO termination is strongly preferred over adsorption on the MnO₂ termination. While moderate doping has a small influence on methanol adsorption and dissociation, when 100% of La is replaced by Sr in the surface or subsurface, the adsorption preference of methanol is reversed. Finally, if the surface is highly dopant enriched, methanol favours dissociative adsorption on the MnO₂-terminated surface.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF); USDOE
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1432170
• Alternate ID(s): OSTI ID: 1550192
• Journal Information: Surface Science, Vol. 664; ISSN 0039-6028
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English