Hydrogen diffusion along grain boundaries in erbium oxide coatings

エルビウム酸化物被膜における水素の粒界拡散

Mao, W.*; 近田 拓未*; 鈴木 晶大*; 寺井 隆幸*; 山口 憲司

Mao, W.*; Chikada, Takumi*; Suzuki, Akihiro*; Terai, Takayuki*; Yamaguchi, Kenji

A tritium permeation barrier (TPB) is required in fusion blanket systems to reduce the loss of fuel and minimize radiological hazard. In this regard, ErO is currently selected as one of the candidate materials for the TPB because of its excellent properties including high permeation reduction factor, good compatibility with liquid lithium, and so on. To understand the microscopic mechanism of hydrogen isotope permeation through TPB, hydrogen (H) diffusion along ErO grain boundaries has been investigated by the experimental and simulated studies. H diffusivity predicted by the simulations was in good agreement with that derived by the experiments. Additionally, interstitial H is predicted to be steadily trapped when it diffuses near a vacancy.