Elucidation of specific adsorption states for ultra-trace-level alkali metals

2015 Fiscal Year Final Research Report

• Project/Area Number: 26630488
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nuclear engineering
• Research Institution: Japan Atomic Energy Agency
• Principal Investigator: Baba Yuji 国立研究開発法人日本原子力研究開発機構, 福島研究開発部門 福島事業管理部, 嘱託 (90360403)
• Co-Investigator(Kenkyū-buntansha): SHIMOYAMA Iwao 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 (10425572) ; HIRAO Norie 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, 技術開発協力員 (30600027)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: セシウム / アルカリ金属 / 吸着 / X線光電子分光法 / 全反射 / 放射光

Outline of Final Research Achievements

In order to elucidate chemical states of radioactive cesium adsorbed on soil and clay, X-ray photoelectron spectra (XPS) were measured for ultra-trace cesium and the other alkali metals adsorbed on oxides and layered oxides (mica). When X-ray was irradiated under total reflection condition, ultra-trace level cesium down to 100 pg/cm2 corresponding to 200 Bq of Cs-137 could be measured by XPS. Core-level chemical shifts in XPS spectra for alkali metals adsorbed on mica were analyzed on the basis of a point-charge model. As a result, it was elucidated that chemical bonds between alkali metals and mica become ionic with the decrease in the thickness of the adsorbed layer.

Free Research Field

表面化学