Zirconium (Zr) alloys as cladding materials are widely used in fission reactors. The service life of Zr-based materials cladding is seriously affected by the hydrogen (H) behaviors; while the impurities (C, N and O) in Zr alloys have a great influence on the hydrogen behaviors. In this work, we have investigated the impurity–hydrogen interactions in hexagonal-closed packed Zr (hcp-Zr) by a first-principles approach. It was found that H atom tends to occupy tetrahedral interstitial position in perfect Zr and occupy octahedral interstitial position in Zr with vacancy, while the impurities tend to occupy octahedral interstitial positions in Zr both with and without vacancy. The impurities can trap H atoms. Four possible paths were studied for the diffusion of H atom in hcp-Zr, and it is found that the diffusion barriers of H varied with the presence of impurities.

锆（Zr）合金作为熔覆材料广泛用于裂变反应堆中。锆基材料熔覆层的使用寿命受到氢（H）行为的严重影响；Zr合金中的杂质（C，N和O）对氢行为有很大的影响。在这项工作中，我们通过第一原理方法研究了六方密堆积Zr（hcp-Zr）中的杂质氢相互作用。研究发现，H原子倾向于在完全Zr中占据四面体间隙位置，在Zr中具有空位时占据八面体间隙位置，而杂质在Zr中无论有无空位都倾向于占据八面体间隙位置。杂质会捕获H原子。研究了h原子在hcp-Zr中扩散的四种可能途径，