Monitoring the in-situ oxide growth on uranium by x-ray photoelectron spectroscopy. (20th September 2019)

• Record Type: Journal Article
• Authors: Sun, Chaolun; Pan, Qifa; Zhong, Huoping; Hu, Yin; Luo, Lizhu; Wang, Xiaofang; Liu, Kezhao
• Is Part Of: Materials research express. Volume 6:Number 10(2019)
• Publication Date: 2019-09-20
• Subjects: XPS -- uranium -- initial oxidation; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/ab4329
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: In the present work, we report the in situ monitoring of oxide growth on metallic uranium surface at room temperature for oxygen pressures from 1 × 10 −7 to 5 × 10 −7 Pa by means of x-ray photoelectron spectroscopy. The oxidation products were analyzed briefly and a quantitative relationship between the oxide film thickness and oxidation time was established and the rate constant was obtained. Results show that the sub-stoichiometric uranium oxides (UO2−x ) were formed, and further transformed to those with smaller x values. We found that oxygen pressure has a positive effect on the rate constant as well as the oxide film thickness, and instead of oxygen pressure, oxygen exposure has a vital impact on determination of the thickness of the oxide layer.