Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
ACS Nano. 2012 Mar 27;6(3):2818-25. doi: 10.1021/nn3003373. Epub 2012 Mar 8.
Formic acid is a promising chemical fuel for fuel cell applications. However, due to the dominance of the indirect reaction pathway and strong poisoning effects, the development of direct formic acid fuel cells has been impeded by the low activity of existing electrocatalysts at desirable operating voltage. We report the first synthesis of Pt(3)Pb nanocrystals through solution phase synthesis and show they are highly efficient formic acid oxidation electrocatalysts. The activity can be further improved by manipulating the Pt(3)Pb-Pt core-shell structure. Combined experimental and theoretical studies suggest that the high activity from Pt(3)Pb and the Pt-Pb core-shell nanocrystals results from the elimination of CO poisoning and decreased barriers for the dehydrogenation steps. Therefore, the Pt(3)Pb and Pt-Pb core-shell nanocrystals can improve the performance of direct formic acid fuel cells at desired operating voltage to enable their practical application.
甲酸是一种很有前途的化学燃料，可用于燃料电池。然而，由于间接反应途径占主导地位，以及强中毒效应，现有的电催化剂在理想工作电压下活性较低，直接甲酸燃料电池的发展受到了阻碍。我们通过溶液法合成首次制备了 Pt(3)Pb 纳米晶体，并证明其是高效的甲酸氧化电催化剂。通过控制 Pt(3)Pb-Pt 核壳结构，可以进一步提高其活性。实验和理论研究表明，Pt(3)Pb 和 Pt-Pb 核壳纳米晶体具有高活性，这是由于消除了 CO 中毒和脱氢步骤的势垒降低。因此，Pt(3)Pb 和 Pt-Pb 核壳纳米晶体可以提高直接甲酸燃料电池在理想工作电压下的性能，从而实现其实际应用。
