Surface structure of iron phosphate glasses with ultra-high chemical durability by X-ray photoelectron spectroscopy

高耐久性を示す鉄リン酸塩ガラスの光電子スペクトル測定による表面構造解析

矢野 哲司*; 赤木 直人*; 柴田 修一*; 天本 一平

Yano, Tetsuji*; Akagi, Naoto*; Shibata, Shuichi*; Amamoto, Ippei

鉄リン酸塩ガラスの化学的耐久性に与える遷移金属酸化物の置換効果について調査し、光電子スペクトル測定によるガラス表面構造と物性との関係について検討した。その結果、クロム酸化物の添加は高い化学的耐久性をもつガラスの作製に大きな効果を持つことを見いだした。さらに、化学的耐久性に影響を与える構造因子について、酸素やリンの電子密度との間に明瞭な関係性が存在することを明らかにした。

In order to clarify the origins of the high chemical durability of iron phosphate glasses and find more stable glass composition, the transition metal oxides were added by the replacement of a part of the iron oxide, prepared the glasses by melt-quenching method and their thermal properties and chemical durabilities were measured. The structures of the glasses and their surfaces were analyzed using X-ray photoelectron spectroscopy. The bulk samples were fractured in vacuum to obtain pristine surfaces, and the photoelectrons emitted from the analyzed surface by the monochromatic X-ray irradiation were collected. From the result, the dissolution rates of the sample glasses were correlated with the structural factors obtained from the XPS data, and strong correlations with the chemical shifts of the core electron spectra of oxygen and phosphorus ions were found, which are on the different trends found in general phosphate glass system like alkali phosphate glass.