Ab-initio calculation of structural and electrical properties of amorphous TiO 2

Binay Prasai; Bin Cai; D. A. Drabold; M. K. Underwood; Ames P. Lewis

Ab-initio calculation of structural and electrical properties of amorphous TiO ₂

Binay Prasai, Bin Cai, D. A. Drabold, M. K. Underwood, Ames P. Lewis

Division of Medical Physics

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › peer-review

8 Scopus citations

Abstract

We used first-principle simulation methods to generate amorphous TiO ₂ (a-TiO ₂) models and obtained chemically-ordered amorphous networks. We analyzed the structural and the electronic properties of the resulting computationally generated structures. We propose that two peaks found in the Ti-Ti pair correlation correspond to the edge-sharing and the corner-sharing Ti-Ti pairs. Resulting coordination numbers for Ti (6) and O (3) and the corresponding angle distributions suggest that local structural features in bulk crystalline TiO ₂ are retained in our a-TiO ₂ models. The electronic density of states and the inverse participation ratio reveal that highly-localized tail states at the valence band edge are due to the displacement of O atoms from the plane containing three neighboring Ti atoms; whereas, the tail states at the conduction band edge are localized on over-coordinated Ti atoms. The Γ-point electronic gap of approximately 2.0 eV is comparable to calculated results for bulk crystalline TiO ₂.

Original language	English
Title of host publication	Materials Science and Technology Conference and Exhibition 2011, MS and T'11
Pages	12-20
Number of pages	9
State	Published - Dec 1 2011
Event	Materials Science and Technology Conference and Exhibition 2011, MS and T'11 - Columbus, OH, United States Duration: Oct 16 2011 → Oct 20 2011

Publication series

Name	Materials Science and Technology Conference and Exhibition 2011, MS and T'11
Volume	1

Conference

Conference	Materials Science and Technology Conference and Exhibition 2011, MS and T'11
Country/Territory	United States
City	Columbus, OH
Period	10/16/11 → 10/20/11

Keywords

Amorphous titania
Properties of titania

Cite this

@inproceedings{7f7e29c263c0420f8ef5bec6397d5004,

title = "Ab-initio calculation of structural and electrical properties of amorphous TiO 2 ",

abstract = "We used first-principle simulation methods to generate amorphous TiO 2 (a-TiO 2) models and obtained chemically-ordered amorphous networks. We analyzed the structural and the electronic properties of the resulting computationally generated structures. We propose that two peaks found in the Ti-Ti pair correlation correspond to the edge-sharing and the corner-sharing Ti-Ti pairs. Resulting coordination numbers for Ti (6) and O (3) and the corresponding angle distributions suggest that local structural features in bulk crystalline TiO 2 are retained in our a-TiO 2 models. The electronic density of states and the inverse participation ratio reveal that highly-localized tail states at the valence band edge are due to the displacement of O atoms from the plane containing three neighboring Ti atoms; whereas, the tail states at the conduction band edge are localized on over-coordinated Ti atoms. The Γ-point electronic gap of approximately 2.0 eV is comparable to calculated results for bulk crystalline TiO 2.",

keywords = "Amorphous titania, Properties of titania",

author = "Binay Prasai and Bin Cai and Drabold, {D. A.} and Underwood, {M. K.} and Lewis, {Ames P.}",

year = "2011",

month = dec,

day = "1",

language = "English",

isbn = "9781618392619",

series = "Materials Science and Technology Conference and Exhibition 2011, MS and T'11",

pages = "12--20",

booktitle = "Materials Science and Technology Conference and Exhibition 2011, MS and T'11",

note = "Materials Science and Technology Conference and Exhibition 2011, MS and T'11 ; Conference date: 16-10-2011 Through 20-10-2011",

}

Prasai, B, Cai, B, Drabold, DA, Underwood, MK & Lewis, AP 2011, Ab-initio calculation of structural and electrical properties of amorphous TiO ₂ in Materials Science and Technology Conference and Exhibition 2011, MS and T'11. Materials Science and Technology Conference and Exhibition 2011, MS and T'11, vol. 1, pp. 12-20, Materials Science and Technology Conference and Exhibition 2011, MS and T'11, Columbus, OH, United States, 10/16/11.

Ab-initio calculation of structural and electrical properties of amorphous TiO ₂ . / Prasai, Binay; Cai, Bin; Drabold, D. A. et al.
Materials Science and Technology Conference and Exhibition 2011, MS and T'11. 2011. p. 12-20 (Materials Science and Technology Conference and Exhibition 2011, MS and T'11; Vol. 1).

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › peer-review

TY - GEN

T1 - Ab-initio calculation of structural and electrical properties of amorphous TiO 2

AU - Prasai, Binay

AU - Cai, Bin

AU - Drabold, D. A.

AU - Underwood, M. K.

AU - Lewis, Ames P.

PY - 2011/12/1

Y1 - 2011/12/1

N2 - We used first-principle simulation methods to generate amorphous TiO 2 (a-TiO 2) models and obtained chemically-ordered amorphous networks. We analyzed the structural and the electronic properties of the resulting computationally generated structures. We propose that two peaks found in the Ti-Ti pair correlation correspond to the edge-sharing and the corner-sharing Ti-Ti pairs. Resulting coordination numbers for Ti (6) and O (3) and the corresponding angle distributions suggest that local structural features in bulk crystalline TiO 2 are retained in our a-TiO 2 models. The electronic density of states and the inverse participation ratio reveal that highly-localized tail states at the valence band edge are due to the displacement of O atoms from the plane containing three neighboring Ti atoms; whereas, the tail states at the conduction band edge are localized on over-coordinated Ti atoms. The Γ-point electronic gap of approximately 2.0 eV is comparable to calculated results for bulk crystalline TiO 2.

AB - We used first-principle simulation methods to generate amorphous TiO 2 (a-TiO 2) models and obtained chemically-ordered amorphous networks. We analyzed the structural and the electronic properties of the resulting computationally generated structures. We propose that two peaks found in the Ti-Ti pair correlation correspond to the edge-sharing and the corner-sharing Ti-Ti pairs. Resulting coordination numbers for Ti (6) and O (3) and the corresponding angle distributions suggest that local structural features in bulk crystalline TiO 2 are retained in our a-TiO 2 models. The electronic density of states and the inverse participation ratio reveal that highly-localized tail states at the valence band edge are due to the displacement of O atoms from the plane containing three neighboring Ti atoms; whereas, the tail states at the conduction band edge are localized on over-coordinated Ti atoms. The Γ-point electronic gap of approximately 2.0 eV is comparable to calculated results for bulk crystalline TiO 2.

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KW - Properties of titania

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