Fabricating the AuPdPt Ternary Nanophase Diagram at 800 °C To Guide the Exploration of Optimal Catalyst for n-Hexane Oxidation

A good knowledge of nanophase diagrams is critical to understanding the performance of nanomaterials. Herein, we for the first time fabricate a AuPdPt ternary nanophase diagram at 800 °C by experimental means. The solid-state synthesis strategy enables a precise synthesis of AuPdPt trimetallic nanoparticles with a full range of compositions and desired size distributions. By studying the phase behavior of those TMNPs, we succeed in mapping out the boundary curve and tie lines. Interestingly, the AuPdPt nanophase boundary shifts obviously to the Au-rich region as compared to the case of the corresponding bulk diagram, likely due to the combination of size and composition effects. Besides, owing to the different solubility of Pd in Au-rich and Pt-rich matrix, some tie lines do not parallel the baseline. These observations greatly improve our basic understanding of nanophase diagrams and are expected to be valuable references for other systems. Moreover, the as-fabricated nanophase diagram is successfully applied to guide the optimization of AuPdPt TMNPs catalysts for n-hexane oxidation.