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

doi:10.1016/j.susc.2017.06.010

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

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Abstract

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.

Authors:

Beste, Ariana ^[1]

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

Publication Date:: 2017-06-20

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)

OSTI Identifier:: 1432170

Alternate Identifier(s):: OSTI ID: 1550192

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Surface Science

Additional Journal Information:: Journal Volume: 664; Journal ID: ISSN 0039-6028

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; perovskite; strontium dopant; LMO; LSMO; VASP; DFT; revPBE; Bader charges

Citation Formats


                    Beste, Ariana. Methanol adsorption and dissociation on LaMnO3 and Sr doped LaMnO3 (001) surfaces.  United States: N. p., 2017. 
        Web.  doi:10.1016/j.susc.2017.06.010.

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                    Beste, Ariana. Methanol adsorption and dissociation on LaMnO3 and Sr doped LaMnO3 (001) surfaces.  United States.  doi:10.1016/j.susc.2017.06.010.

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                    Beste, Ariana. Tue .  
        "Methanol adsorption and dissociation on LaMnO3 and Sr doped LaMnO3 (001) surfaces".  United States.  doi:10.1016/j.susc.2017.06.010.  https://www.osti.gov/servlets/purl/1432170.

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@article{osti_1432170,

  title        = {Methanol adsorption and dissociation on LaMnO3 and Sr doped LaMnO3 (001) surfaces},

  author       = {Beste, Ariana},

  abstractNote = {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.},

  doi          = {10.1016/j.susc.2017.06.010},

  journal      = {Surface Science},

  number       = ,

  volume       = 664,

  place        = {United States},

  year         = {2017},

  month        = {6}

}

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DOI: 10.1016/j.susc.2017.06.010

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

Abstract

Citation Formats

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