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对氢气分子在Sc和Y共掺杂的Mg(0001)面的解离情况进行了系统的研究,采用的研究法是利用基于密度泛函理论的第一性原理计算。对Sc原子和Y原子共同掺杂在Mg(0001)表面的稳定替代位置进行了研究,发现Sc原子和Y原子将选择共同停留在第一层并且是相邻的位置时最稳定。氢气分子在由Sc和Y共同掺杂的Mg(0001)表面解离时,其解离势垒被降低至0.05 eV。利用分波态密度分析了氢气分子在其表面分解的过渡态时的电子分布,通过分析发现,Sc原子及Y原子的d带电子与H原子的s带电子发生了明显的作用,其中Sc原子的d带电子的贡献起主要作用。研究表明,Sc和Y共同掺杂可以有效提高镁基储氢材料的吸放氢动力学性能,是改善镁基储氢材料的动力学性能很好的催化剂。
The dissociation of hydrogen molecules in Sc and Y co-doped Mg (0001) planes has been studied systematically. The research method is based on the first principles calculations based on density functional theory. We have studied the stable substitution of Sc atoms and Y atoms co-doping on the Mg (0001) surface and found that the Sc atoms and the Y atoms will choose to co-stay in the first layer and are the most stable adjacent sites. Hydrogen molecules dissociate on the Mg (0001) surface co-doped by Sc and Y, and their dissociation barrier is reduced to 0.05 eV. The distribution of hydrogen molecules in the transition state of their surface decomposition was analyzed by using the decoupled-state density. The d-band electron of Sc atom and Y atom obviously interacted with the s-band electron of H atom. The Sc atom The contribution of d with electrons plays a major role. The results show that co-doping Sc and Y can effectively improve the kinetics of hydrogen storage and desorption of Mg-based hydrogen storage materials and is a good catalyst for improving the kinetic performance of Mg-based hydrogen storage materials.