Hydrogen trapping in oxygen-deficient hafnium silicates

Isotopic substitution, nuclear reaction analysis, and x-ray photoelectron spectroscopy were employed to show that oxygen-deficient hafnium (Hf) silicates trap hydrogen atoms. Based on this experimental observation, we used first-principles calculations to investigate the structure, energetics, and e...

Full description

Saved in:
Bibliographic Details
Published in:Journal of applied physics 2007-08, Vol.102 (4), p.044108-044108-6
Main Authors: Fonseca, L. R. C., Xavier, A. L., Ribeiro, M., Driemeier, C., Baumvol, I. J. R.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Isotopic substitution, nuclear reaction analysis, and x-ray photoelectron spectroscopy were employed to show that oxygen-deficient hafnium (Hf) silicates trap hydrogen atoms. Based on this experimental observation, we used first-principles calculations to investigate the structure, energetics, and electronic properties of H interacting with O vacancies in a hafnium silicate model. We found that O vacancies close to a Si atom are energetically favored when compared to vacancies in HfO 2 -like regions, implying that close-to-Si O vacancies are more likely to occur. Trapping of two H atoms at a close-to-Si O vacancy passivates the vacancy-induced gap states. The first H interacts with neighboring Hf atoms, whereas the second H binds to the Si atom.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.2769790