Roles of Pb and MnOx in PtPb/MnOx-CNTs catalyst for methanol electro-oxidation
Roles of Pb and MnOx in PtPb/MnOx-CNTs catalyst for methanol electro-oxidation
复制标题
PtPb/MnOx-CNTs 甲醇电氧化催化剂中 Pb 和 MnOx 的作用
DOI：
10.1016/j.ijhydene.2011.10.002
复制
发表时间：
2012-01-01
影响因子：
7.2
通讯作者：
Guo, Yonglang
中科院分区：
文献类型：
--
作者：
Huang, Yiyin;Cai, Jindi;Guo, Yonglang
设计高活性、低成本的新型纳米甲醇氧化催化剂对直接甲醇燃料电池的发展至关重要。在本研究中，为了制备PtPb/MnOx-CNTs催化剂，被迫在碳纳米管表面先后沉积了MnOx、铂和铅。物理表征表明，该催化剂中存在大量的Mn(IV，V)、Pb(II)和Pt(0)物种，并存在部分合金化。该复合材料的甲醇氧化反应比活性(140.9 mA cm-2)和起始电位(-0.1V vs.Hg/Hg2SO4)分别为铂/碳纳米管的44.2mA cm(-2)和0V的3倍以上。对反应机理的基本了解使我们能够揭示铅和MnOx在甲醇氧化过程中的区别作用。铅的加入提高了残留中间物种的本征电氧化活性，而以MnOx-CNTs为载体的甲醇氧化过程中的脱氢反应明显改善。版权所有(C)2011，氢能出版有限责任公司。爱思唯尔有限公司出版。保留所有权利。
Design of novel nano-scale catalysts with high activity and low cost for methanol oxidation reaction is crucial for the development of direct methanol fuel cell. In this study, MnOx Pt and Pb were forced to precipitate successively on the surface of carbon nanotubes for fabricating a PtPb/MnOx-CNTs catalyst. Physical characterizations indicated that there existed a mass of Mn (IV, V), Pb (II) and Pt (0) species, and partial alloying between Pt and Pb in this catalyst. Methanol oxidation reaction with this novel composite exhibited over 3 times higher specific activity (140.9 mA cm(-2)) and somewhat lower onset potential (-0.1 V vs. Hg/Hg2SO4) than the values on Pt/CNTs (44.2 mA cm(-2) and 0 V, respectively). Fundamental understanding in reaction mechanisms enabled us to reveal the distinguishing functions between Pb and MnOx in methanol oxidation processes. The addition of Pb resulted in the enhanced intrinsic activity towards electro-oxidation of residual intermediate species, while dehydrogenation in methanol oxidation processes was obviously improved by using MnOx-CNTs as a support. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.