α-Al₂O₃ based coatings are the first candidate for tritium permeation barriers (TPBs) in fusion reactors, and the impurity effect on hydrogen resistance is one of the major concerns. In the present work, Fe effect on hydrogen interactions with intrinsic point defects and hydrogen migration in α-Al₂O₃ under the TPB service condition has been investigated based on first-principles calculations. It is found that Fe is unfavorable for the formation of vacancy-type defects and defect complex [V_Al-H] in α-Al₂O₃, yet beneficial for the formation of H-related defects H_i and H_O. The H trapping ability by vacancy type defects in α-Al₂O₃ is lowered after Fe doping. H_i is the main diffusion species in Fe-doped α-Al₂O₃, and Fe is favorable for the H migration in α-Al₂O₃, which will be unfavorable for H resistance of α-Al₂O₃ based TPBs. During the H_i migration in Fe-doped α-Al₂O₃, one step of screw motion is involved, in which the forming and breaking of the H-Fe and H-O bonds occur.

的α-Al _2种ö ₃基涂层是用于聚变反应堆氚渗透屏障（TPBS）第一候选，并在氢电阻杂质效应是主要关心的问题之一。另外，在本工作中，铁效果上氢相互作用与本征点缺陷和氢迁移的α-Al ₂ ö ₃的TPB服务条件下已经研究了基于第一原理计算。据发现，Fe为不利的空位型缺陷的形成和缺陷复[V_铝-H]在的α-Al ₂ ö ₃，但有益的H-相关缺陷的形成ħ_我和H _ö。在α-Al系由空位型缺陷为H捕获能力₂ ö ₃为Fe掺杂后降低。ħ_我是在Fe掺杂的主要扩散物种的α-Al ₂ ö ₃，和Fe是利于在H迁移的α-Al ₂ ö ₃，这将是不利的的H电阻的α-Al _2个ö _3个基于TPBS 。在ħ_我在迁移Fe掺杂的α-Al ₂ ö ₃，螺杆运动的一个步骤涉及，其中，所述成形和H-Fe和HO键的断裂发生。