高热稳定性铂基纳米合金催化剂的构筑及其催化甲烷部分氧化制合成气反应研究

Partial oxidation of methane (POM) is a cheap way to produce synthesis gas which requires high thermally stable precious metal catalysts. We recently discovered that MgAl2O4 spinel {111} nano-facets are capable of stabilizing small Pt nanoparticles below 3 nm at 800 oC, whose thermal stability meets the requirement for POM reaction. In this project we aim to design Pt-based nano-alloy catalysts which have high thermal stability, catalytic activity and selectivity for POM reaction by modifying the surface structure of Pt using secondary metals that have much higher reactivity and selectivity for POM reaction. We will study the relationships between the synthesis methods and the derived structures and the reaction kinetics by combining the characterizations with advance techniques and the measurements of reaction kinetics as well as DFT calculations. Furthermore, we will try to reveal the reaction mechanism of POM on the stable Pt-based nano-alloy catalysts. This project is expected to contribute to both fundamental and applied fields of catalysis. In fundamental science, it will expand the studies on structure-function relationships in conventional low and mild reaction temperature regions to high temperture regions. On the other hand, in the potential applications, it will provide a practical way for cheaply producing synthesis gas via partial oxidation of methane.

甲烷部分氧化法廉价制取合成气需要具有高热稳定性的贵金属催化剂。申请人近期发现MgAl2O4{111}晶面上Pt粒子能在800oC保持尺寸小于3纳米，满足上述反应对催化剂热稳定性的要求。本项目将针对甲烷部分氧化制取合成气反应，以高热稳定性的Pt/MgAl2O4{111}结构为主体，与少量对该反应比Pt具有更高活性和选择性的异种金属形成体相或表面纳米合金，调变Pt颗粒的表面几何结构和电子结构，设计兼具高热稳定性、高活性和高选择性的催化剂。结合多种结构表征技术和反应动力学测定以及DFT理论计算，研究Pt基纳米合金制备方法与所得催化剂结构及催化功能之间的关系，深入研究甲烷部分氧化在结构稳定的贵金属纳米合金催化剂上的反应机制。本项目的实施，在基础研究领域有望将在中低温领域的贵金属催化剂结构与功能关系研究扩展到高温领域；在工业应用方面将为甲烷部分氧化廉价制取合成气提供可行的途径。