Hydration and reduction of molecular beam epitaxy grown vo x/α-fe 2o 3(0001): ambient pressure study

Chang Yong Kim; Jeffrey A. Klug; Peter C. Stair; Michael J. Bedzyk

doi:10.1021/jp804133s

Hydration and reduction of molecular beam epitaxy grown vo _x/α-fe ₂o ₃(0001): ambient pressure study

Chang Yong Kim, Jeffrey A. Klug, Peter C. Stair, Michael J. Bedzyk

Research output: Contribution to journal › Article › peer-review

5 Scopus citations

Abstract

Supported vanadium oxides processed under ambient environments have been studied by using X-ray standing wave (XSW) analysis of X-ray fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS). For the VO _x/α-Fe ₂O ₃(0001) system, hydration and hydrogen annealing have been carried out under ambient pressure. Vanadium in the hydrated oxide phase occupies two high-symmetry surface adsorption sites with distinct adsorption heights, which resembles the adsorption geometry of fully oxidized vanadium. Reduction by the hydrogen annealing enhanced the V overlayer ordering by relocating a portion of the disordered V to highsymmetry sites. The V atoms located closer to the substrate oxygen layer in the hydrated phase moved toward the substrate after hydrogen reduction, while the V in the higher adsorption site stayed at the same height. The different responses of two adsorption sites to the reduction process are discussed and related to activities of the two sites

Original language	English (US)
Pages (from-to)	1406-1410
Number of pages	5
Journal	Journal of Physical Chemistry C
Volume	113
Issue number	4
DOIs	https://doi.org/10.1021/jp804133s
State	Published - Jan 29 2009

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials
Energy(all)
Physical and Theoretical Chemistry
Surfaces, Coatings and Films

Access to Document

10.1021/jp804133s

Cite this

@article{53f38d3da5b440bf9b7544f49e4d39e6,

title = "Hydration and reduction of molecular beam epitaxy grown vo x/α-fe 2o 3(0001): ambient pressure study",

abstract = "Supported vanadium oxides processed under ambient environments have been studied by using X-ray standing wave (XSW) analysis of X-ray fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS). For the VO x/α-Fe 2O 3(0001) system, hydration and hydrogen annealing have been carried out under ambient pressure. Vanadium in the hydrated oxide phase occupies two high-symmetry surface adsorption sites with distinct adsorption heights, which resembles the adsorption geometry of fully oxidized vanadium. Reduction by the hydrogen annealing enhanced the V overlayer ordering by relocating a portion of the disordered V to highsymmetry sites. The V atoms located closer to the substrate oxygen layer in the hydrated phase moved toward the substrate after hydrogen reduction, while the V in the higher adsorption site stayed at the same height. The different responses of two adsorption sites to the reduction process are discussed and related to activities of the two sites",

author = "Kim, {Chang Yong} and Klug, {Jeffrey A.} and Stair, {Peter C.} and Bedzyk, {Michael J.}",

year = "2009",

month = jan,

day = "29",

doi = "10.1021/jp804133s",

language = "English (US)",

volume = "113",

pages = "1406--1410",

journal = "Journal of Physical Chemistry C",

issn = "1932-7447",

publisher = "American Chemical Society",

number = "4",

}

TY - JOUR

T1 - Hydration and reduction of molecular beam epitaxy grown vo x/α-fe 2o 3(0001)

T2 - ambient pressure study

AU - Kim, Chang Yong

AU - Klug, Jeffrey A.

AU - Stair, Peter C.

AU - Bedzyk, Michael J.

PY - 2009/1/29

Y1 - 2009/1/29

N2 - Supported vanadium oxides processed under ambient environments have been studied by using X-ray standing wave (XSW) analysis of X-ray fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS). For the VO x/α-Fe 2O 3(0001) system, hydration and hydrogen annealing have been carried out under ambient pressure. Vanadium in the hydrated oxide phase occupies two high-symmetry surface adsorption sites with distinct adsorption heights, which resembles the adsorption geometry of fully oxidized vanadium. Reduction by the hydrogen annealing enhanced the V overlayer ordering by relocating a portion of the disordered V to highsymmetry sites. The V atoms located closer to the substrate oxygen layer in the hydrated phase moved toward the substrate after hydrogen reduction, while the V in the higher adsorption site stayed at the same height. The different responses of two adsorption sites to the reduction process are discussed and related to activities of the two sites

AB - Supported vanadium oxides processed under ambient environments have been studied by using X-ray standing wave (XSW) analysis of X-ray fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS). For the VO x/α-Fe 2O 3(0001) system, hydration and hydrogen annealing have been carried out under ambient pressure. Vanadium in the hydrated oxide phase occupies two high-symmetry surface adsorption sites with distinct adsorption heights, which resembles the adsorption geometry of fully oxidized vanadium. Reduction by the hydrogen annealing enhanced the V overlayer ordering by relocating a portion of the disordered V to highsymmetry sites. The V atoms located closer to the substrate oxygen layer in the hydrated phase moved toward the substrate after hydrogen reduction, while the V in the higher adsorption site stayed at the same height. The different responses of two adsorption sites to the reduction process are discussed and related to activities of the two sites

UR - http://www.scopus.com/inward/record.url?scp=65249150792&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=65249150792&partnerID=8YFLogxK

U2 - 10.1021/jp804133s

DO - 10.1021/jp804133s

M3 - Article

AN - SCOPUS:65249150792

VL - 113

SP - 1406

EP - 1410

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 4

ER -

Hydration and reduction of molecular beam epitaxy grown vo _x/α-fe ₂o ₃(0001): ambient pressure study

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this