First principles study of gallium-cleaning for hydrogen-contaminated α-Al2O3(0001) surfaces

Authors

Rui Yang, Australian National UniversityFollow
Alistair P. Rendell, Australian National University

RIS ID

77453

Publication Details

Yang, R. & Rendell, A. P. (2013). First principles study of gallium cleaning for hydrogen-contaminated α-Al2O3(0001) surfaces. Journal of Computational Chemistry, 34 (13), 1101-1111.

Abstract

The use of gallium for cleaning hydrogen-contaminated Al2O 3 surfaces is explored by performing first principles density functional calculations of gallium adsorption on a hydrogen-contaminated Al-terminated α-Al2O3(0001) surface. Both physisorbed and chemisorbed H-contaminated α-Al2O 3(0001) surfaces with one monolayer (ML) gallium coverage are investigated. The thermodynamics of gallium cleaning are considered for a variety of different asymptotic products, and are found to be favorable in all cases. Physisorbed H atoms have very weak interactions with the Al 2O3 surface and can be removed easily by the Ga ML. Chemisorbed H atoms form stronger interactions with the surface Al atoms. Bonding energy analysis and departure simulations indicate, however, that chemisorbed H atoms can be effectively removed by the Ga ML. © 2013 Wiley Periodicals, Inc.