Oxidation of noble metals in gamma-ray radiation environment

2015 Fiscal Year Final Research Report

• Project/Area Number: 25420744
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Composite materials/Surface and interface engineering
• Research Institution: Japan Atomic Energy Agency
• Principal Investigator: YAMAMOTO SHUNYA 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門 量子ビーム応用研究センター, 研究主幹 (70354941)
• Co-Investigator(Kenkyū-buntansha): HAKODA TERUYUKI 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門・量子ビーム応用研究センター, 研究主幹 (70354933)
• Co-Investigator(Renkei-kenkyūsha): SHMADA AKIHIKO 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門・量子ビーム応用研究センター, 技術員 (50354931)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ガンマ線 / 貴金属 / 酸化物 / 薄膜 / ガスセンサー / 触媒

Outline of Final Research Achievements

We investigated the influence of γ-ray radiation on noble metal films to obtain new knowledge about catalysis that can be used in a γ-ray radiation environment for hydrogen gas sensors. The epitaxial films of the noble metals (Ru, Rh, Pd, Ag, Ir, Pt, and Au) were prepared by sputtering deposition. The thin films were irradiated with 60Co γ-ray (～5 MGy) in air. We found that oxidation of Pd and Ag epitaxial films occurred with γ-ray radiation more than 1 MGy. The results suggested that oxidation of Pd and Ag films was related to nitric acid in air produced by 60Co γ-ray radiation. In contrast, oxidation of Pt, Au, Rh, Ru, and Ir epitaxial films by γ-ray irradiation could not be confirmed. Thus, these noble metals are possible to use in catalysis in a γ-ray radiation environment.

Free Research Field

材料工学