In this work the relationship between structural composition and electrochemical characteristics of Palladium(Pd)-Ruthenium(Ru) nanoparticles during alkaline methanol oxidation reaction is investigated. The comparative study of a standard alloyed and a precisely Ru-core-Pd-shell structured catalyst allows for a distinct investigation of the electronic effect and the bifunctional mechanism. Core-shell catalysts benefit from a strong electronic effect and an efficient Pd utilization. It is found that core-shell nanoparticles are highly active towards methanol oxidation reaction for potentials ≥0.6 V, whereas alloyed catalysts show higher current outputs in the lower potential range. However, differential electrochemical mass spectrometry (DEMS) experiments reveal that the methanol oxidation reaction on core-shell structured catalysts proceeds via the incomplete oxidation pathway yielding formaldehyde, formic acid or methyl formate. Contrary, the alloyed catalyst benefits from the Ru atoms at its surface. Those are found to be responsible for high methanol oxidation activity at lower potentials as well as for complete oxidation of CH₃OH to CO₂ via the bifunctional mechanism. Based on these findings a new Ru-core-Pd-shell-Ru-terrace catalyst was synthesized, which combines the advantages of the core-shell structure and the alloy. This novel catalyst shows high methanol electrooxidation activity as well as excellent selectivity for the complete oxidation pathway.

在这项工作中，研究了碱性甲醇氧化反应过程中钯（Pd）-钌（Ru）纳米粒子的结构组成与电化学特性之间的关系。对标准合金和精确Ru-核-Pd-壳结构催化剂的比较研究可以对电子效应和双功能机理进行独特的研究。核-壳型催化剂得益于强大的电子效应和有效的Pd利用率。发现核-壳纳米粒子在电势≥0.6V时对甲醇氧化反应具有很高的活性，而合金催化剂则在较低的电势范围内显示出较高的电流输出。然而，差示电化学质谱法（DEMS）实验表明，核-壳结构催化剂上的甲醇氧化反应通过不完全的氧化途径进行，从而生成甲醛，甲酸或甲酸甲酯。相反，合金化催化剂得益于其表面的Ru原子。已发现这些物质负责在较低电势下具有较高的甲醇氧化活性，并导致CH的完全氧化通过双功能机理将₃ OH转化为CO ₂。基于这些发现，合成了一种新的Ru-核-Pd-壳-Ru-露台催化剂，结合了核-壳结构和合金的优点。这种新型催化剂显示出高的甲醇电氧化活性以及对完整氧化途径的优异选择性。