Zr(0001)表面氢吸附的第一性原理研究  

First-Principles Study of Hydrogen Absorption on Zr(0001) Surface

作　　者：宋伊 冯焱[1] 成永军[1] 裴晓强[1] 冯天佑[1] 董猛[1] 魏宁斐 邱云涛 Song Yi;Feng Yan;Cheng Yongjun;Pei Xiaoqiang;Feng Tianyou;Dong Meng;Wei Ningfei;Qiu Yuntao(Science and Technology on Vacuum Technology and Physics Laboratory,Lanzhou Institute of Physics,Lanzhou 730000,China)

机构地区：[1]兰州空间技术物理研究所,真空技术与物理重点实验室,甘肃兰州730000

出　　处：《稀有金属材料与工程》2022年第1期143-148,共6页Rare Metal Materials and Engineering

摘　　要：利用基于密度泛函理论的第一性原理,采用平面波赝势方法,研究了H_(2)分子在Zr(0001)晶面的表面吸附。通过研究Zr(0001)/H_(2)体系的吸附能、稳定吸附构型和电子结构,阐明了Zr(0001)表面吸氢反应的微观机制。结果表明:H_(2)分子在Zr(0001)表面的最稳定吸附位为面心立方(fcc)位,其吸附能为0.899 eV,解离的H原子最终稳定吸附在Zr(0001)表面的穴(hollow)位和面心立方(fcc)位。被吸附H原子与Zr(0001)表面间出现了大量的电荷转移,同时,H原子的1s轨道和Zr原子的5s、4d轨道出现杂化,表明H;分子解离吸附后H原子与表层Zr原子间同时存在离子键和共价键。吸附能随覆盖度的增大而增大,当覆盖度达到4/5 ML时,氢分子解离后有一半的氢原子吸附到Zr(0001)的亚表面。The adsorption of H_(2) on Zr(0001) crystal surface was studied by the first-principles plane wave pseudopotential method within the density functional theory. By calculating the preferred adsorption sites, adsorption energy and electronic structure of Z(0001)/H_(2) system, the microscopic mechanism for adsorption of H_(2) on Zr(0001) surface was clarified. The results show that the favourable adsorption position of H_(2) on Zr(0001) surface is the fcc site and its adsorption energy is 0.899 eV belonging to a strong chemical adsorption, and the two H atoms dissociated from H_(2) molecules are finally stably adsorbed at the hollow and fcc sites on the surface of Zr(0001). There is a large amount of charge transfer between the adsorbed H atom and Zr(0001) surface, which results in the formation of ionic bond between H and Zr atom, and the typical covalent bonds between H and surface Zr form through the orbital hybridization of H 1 s and Zr 5 s, 4 d. As a result, one can see that the chemical bonding between the H atom and the surface Zr atom is a characteristic mixture of the ionic and covalent bonding. In addition, the adsorption energy gradually increases with the increase of coverage. When the coverage increases to 4/5 ML, half of H atoms after the dissociation of H_(2) are adsorbed on the subsurface of Zr(0001).

关 键 词：第一性原理 Zr(0001)表面 氢吸附 稳定吸附构型 电子结构 

分 类 号：TL341[核科学技术—核技术及应用] TG146.414[一般工业技术—材料科学与工程]