Highly alloyed PtRu black electrocatalysts for methanol oxidation prepared using magnesia nanoparticles as sacrificial templates
Highly alloyed PtRu black electrocatalysts for methanol oxidation prepared using magnesia nanoparticles as sacrificial templates
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DOI：
10.1016/j.jpowsour.2013.09.086
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发表时间：
2014-02
影响因子：
9.2
通讯作者：
Liangliang Zou;Jing Guo;Juanyi Liu;Z. Zou;D. Akins;Hui Yang
中科院分区：
文献类型：
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作者：
Liangliang Zou;Jing Guo;Juanyi Liu;Z. Zou;D. Akins;Hui Yang
合成用于直接甲醇燃料电池的小颗粒、高合金化的PtRu黑催化剂仍然是一个巨大的挑战。本工作以纳米氧化镁为牺牲模板剂，以铂和RuCl3为起始前驱体，合成了PtRu(1：1)黑色催化剂。氧化镁用于防止合成的PtRu纳米粒子在热处理过程中的团聚，从而促进高合金成分、小颗粒尺寸的PtRu黑的可控形成。X-射线衍射分析表明，PtRu黑色纳米粒子具有单相的面心立方结构，且合金化程度随处理温度的升高而增加。经250~300℃热处理的PtRu黑催化剂的平均粒径约为3 nm，仅略大于商品Johnson-MatthePtRu黑，但合金化程度更高。电化学测试表明，自制的PtRu黑催化剂对甲醇氧化的催化活性约为商品催化剂的两倍，具有更好的耐久性，表明铂、Ru之间的合金化程度对提高催化剂的催化活性和耐久性具有重要作用。
Synthesis of small particle size, highly alloyed PtRu black catalysts for application in direct methanol fuel cells remains a substantial challenge. In this work, PtRu (1:1) black catalysts have been synthesized using Pt carbonyl complex and RuCl3as initial precursors and magnesia nanoparticles as sacrificial templates. Magnesia is used to prevent the aggregation of synthesized PtRu nanoparticles during heat treatment, and thus promoting the controllable formation of PtRu black of high alloy composition and small particle size. X-ray diffraction shows that the PtRu black nanoparticles have a single-phase face-centered cubic structure and that the degree of alloying increases with treatment temperature. The mean particle size of the PtRu black catalysts, after heat-treatment from 250 to 300 °C, is found to be ca. 3 nm, only slightly larger than that of commercial Johnson-Matthey PtRu black, but more highly alloyed. Electrochemical measurements indicate that the catalytic activity for methanol oxidation on in-house prepared PtRu black catalysts is about twice that of the commercial product, with greater durability, indicating that the degree of alloying between Pt and Ru plays an important role in improving both catalytic activity and durability of the catalysts when used for methanol oxidation.