Pd对O吸附在ZnO(0001)面上的影响的第一性原理研究

First-pinciples studies for the effects of Pd on oxgen atoms adsorbed on ZnO(0001) surface

本文用第一性原理方法计算了Pd在ZnO(0001)面上的吸附、Pd对O吸附的影响及Pd替代表面Zn原子能量的变化.结果表明:(1)Pd的吸附位置不随覆盖度变化,Pd稳定吸附位为H3位;(2)Pd在1/4单层吸附时比1个单层吸附时稳定;(3)Pd的存在增强了氧在ZnO(0001)面上的吸附,O原子可以扩散到Pd吸附层的下,Pd处于最上面,具有催化作用.

The adsorption properties of Pd on ZnO(0001) surface are studied using the first principle projector-augmented-wave (PAW) method based density functional theory (DFT) within generalized gradient approximation (GGA). The different structures of Pd adsorbed on ZnO(0001) surfaces are considered . It is found that; (l)Pd prefers to be adsorbed on H_3 site with different coverage; (2) Of our calculations the most energetically favorable structure is Pd adsorbate at H_3 site on ZnO(0001)-(2× 2) with 0.25 monolayers coverage; (3) Pd adlayer on the ZnO(0001) enhances O adsorption. The total energy calculations show that O adatom may diffuse below Pd adlayer. Pd may as a function of catalyst in the growth of the ZnO.