氢气在Ti原子掺杂的镁薄膜表面的解离和扩散研究

Study on Dissociation and Diffusion of Hydrogen on Surface of Magnesium Thin Film Doped with Ti Atoms

基于密度泛函理论计算,研究了氢气分子与Ti原子掺杂的镁薄膜表面的相互作用。结果表明,Ti原子替代在镁薄膜表面第二层的位置最稳定。氢气在Ti原子掺杂的镁薄膜表面(Ti原子替代在第二层)的解离势垒下降至0.76e V。第1个氢原子扩散势垒是0.11 e V,氢原子离开Ti原子扩散至更远的位置,而不是吸附在Ti原子旁边;催化剂原子不会与先解离的氢气原子成键。研究表明,掺杂Ti的镁薄膜是一种拥有良好性能的储氢材料。

Based on the calculation of density functional theory, the interaction between the hydrogen molecule and （0001） surface of magnesium thin film doped with and Ti atoms was studied. The results show that Ti atom substituted in the second layer on the surface of the magnesium thin film is the most stable, and the dissociation potential barrier of hydrogen molecule on the Ti-doped magnesium film descends to 0.76 eV. The diffusion barrier of the first hydrogen atom is 0.11 eV, the hydrogen atom diffuses from the Ti atom to a further position, not by the side of the Ti atom. The catalyst atom does not bond with the hydrogen atom of the first dissociation. The results show that the magnesium thin film doped with Ti is a kind of hydrogen storage material with good performance.