由于贵金属多元合金体系相图的研究严重不足，制约了贵金属新材料的设计、开发及应用。本项目选择在直接醇类燃料电池催化材料领域有较强的应用背景的Au-Pt-X(X=Sn,Ni)两个体系，开展块体和纳米相图的研究。首先拟分别采用扩散多元节和扩散偶法研究Au-Pt-X(X=Sn,Ni)两个体系的相平衡关系；然后采用第一性原理与计算相图相结合的方法计算并优化体系块体相图并建立体系热力学数据库；最后，在块体相图研究的基础上,通过计算与实验相结合的方法构建体系纳米相图。在此基础上，为解决贵金属强化以及纳米催化剂稳定性的调控问题，重点研究合金元素Sn、Ni对Au-Pt体系调幅分解热力学与动力学的影响规律，以及纳米粒子尺寸和成分分布对催化剂稳定性的控制规律，探索贵金属块体合金材料的有效强化机制，阐明多金属间协同作用纳米体系稳定性的调控机理，为新型贵金属纳米催化材料的设计及工业应用提供必要的理论指导。

The phase diagram of multicomponent precious metals alloy system is seriously inadequate, which has restricted the design, application and development of new precious metals materials. In this research, Au-Pt-X(X=Sn,Ni) systems which have wide application background in direct alcohol fuel cell catalysis field will be chosen, and the phase diagram of bulk and nanoparticles will be studied. Firstly, the phase equilibrium of Au-Pt-X(X=Sn,Ni) systems will be measured by diffusion multisection method and diffusion couple method respectively; Secondly, Au-Pt-X(X=Sn,Ni) systems phase diagram will be calculated and optimized by first principles calculation combine with CALPHAD method, and the thermodynamic database of systems will be obtained; Finally, based on the bulk alloy system phase diagram, the phase diagram of Au-Pt-X(X=Sn,Ni) nanoparticles system will be studied by CALPHAD method and experiment research. After that, in order to solve the problems of precious metals strengthening and stabilization of precious metals nano-catalyst, the emphatic research will be put on the effect law of Sn, Ni on thermodynamics and kinetics of Au-Pt spinodal decomposition, as well as the influence rule of nanoparticle size and composition on the stability of catalysts, and a valid strengthening mechanism for precious metals will be proposed, the regulation mechanism of the stability of the nano-system with the synergistic effect of multi-metal will be illuminated, thus can provide the theoretical guidance for designing and application of the direct alcohol fuel cell precious metals catalytic materials.