部分含Pt和Ag的贵金属体系相图热力学计算

【作者】 王金三；

【导师】 刘华山；

【作者基本信息】 中南大学 ， 材料学， 2010， 硕士

【摘要】 Pt系和Ag系贵金属催化剂在现代工业中具有广泛的应用前景。为了给Pt和Ag催化剂性能的研究和改进提供理论上的依据,有必要对相关体系进行热力学优化以便获得精确的相图和热力学数据。本文结合第一原理计算,以CALPHAD方法对Pt-Ga-Ge和Ag-Ga-Ge两个三元系进行了热力学优化计算,建立了白洽的热力学数据库。主要研究工作如下：1.运用第一原理计算了Pt-Ga-Ge体系中各个二元系的中间相(包括稳定相与可能的亚稳相)的形成焓,获得了合理的计算结果。2.在第一原理计算结果的基础上,优化和计算了Pt-Ge,Pt-Ga,Ga-Ge三个二元系。结合文献报道的实验数据外推优化了Pt-Ga-Ge二元系,计算了液相面投影图与一系列等温截面。3.优化和计算了Ag-Ga和Ag-Ge两个二元系。结合本文优化的Ga-Ge二元系,外推计算了Ag-Ga-Ge三元系和液相面投影图及其一系列等温截面。更多还原

【Abstract】 The precious metals, Pt, Ag and their alloys, have been widely used as catalysts in modern industry. Establishment of the thermodynamic database of Pt and/or Ag alloys is very important to improve the catalyzing capability of related system. In this work, thermodynamic assessments of Pt-Ga-Ge and Ag-Ga-Ge ternary systems were performed by combining First-Principles with CALPHAD.1. Formation enthalpies of compounds including stable and hypothetical phases in Pt-Ga-Ge system were calculated by First-Principles method.2. On the basis of the results from First-Principles calculation, the Pt-Ge and Pt-Ga binary system was optimized. Combined with the reassessed parameters of the Ga-Ge binary system in this work, the Pt-Ga-Ge ternary system was extrapolated. The liquid project and several isothermal sections were calculated3. The Ag-Ga and Ag-Ge binary systems were reassessed. Combined with the optimized parameters of the Ga-Ge binary system in this work, the Ag-Ga-Ge ternary system was extrapolated. The liquid project and several isothermal sections were calculated.更多还原