Pt(100)/ZrO2(100)界面性质的第一性原理

采用密度泛函理论的平面波赝势法,分别研究在ZrO2(100)面上以氧为键桥和以锆为键桥的Pt(100)/ZrO2(100)界面模型的结合能、电子结构以及等电荷差分密度分布图。结果发现:在以氧为键桥的Pt(100)/ZrO2(100)-bridgeO界面结合能为1.978J/m2,而以锆为键桥的Pt(100)/ZrO2(100)-bridgeZr界面结合能为10.035J/m2,前者的界面结合能低于后者的界面结合能,即以锆为键桥的ZrO2(100)更容易与Pt(100)面结合。通过电子结构和等电荷差分密度分布图分析可知,以氧为键桥的Pt(100)/ZrO2(100)-bridgeO时,主要是锆氧之间存在电子转移,而以锆为键桥的Pt(100)/ZrO2(100)-bridgeZr时,不仅锆氧之间、而且铂锆之间也存在电子转移,铂锆之间主要是锆的4d电子轨道和铂的5d以及部分6s、5p电子轨道上的电子发生了转移并且成键结合,这说明在铂基材料中以锆为键桥的界面结合能有效提高铂基材料的强度。

First-Principles Study of the Interface Properties of Pt(100)/ZrO2(100)

Using the pseudopotential plane-wave method of the density-functional theory (DEF), the interface energy, electron structure and contour of the charge density of the Pt(100)/ZrO2(100) interface model with the bridge O and bridge Zr in ZrO2(100) were investigated. Results show that the Pt(100)/ZrO2(100)-bridge O interface energy with bridge O is 1.978 J/m2, and the Pt(100)/ZrO2(100)-bridge Zr interface energy with bridge Zr is 10.035 J/m2, indicating that the energy of bridge O is lower than the energy of bridge Zr, i.e. the ZrO2(100) with bridge Zr is easy to combine with the Pt(100). By the electron structure and contour of the charge density, there is mainly electron transfer between Zr and O with the Pt(100)/ZrO2(100)-bridge O; however, there is electron transfer between Zr and O and between Pt and Zr with the Pt(100)/ZrO2(100)-bridge Zr; between Pt and Zr there is the 4d electron orbit of Zr and the 5d and part of 6s and 5p electron orbit of Pt and they are combined. The results demonstrate that the strength of the platinum based-materials can be increased by Zr bridge interface bonding.