Department of Chemical & Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
J Am Chem Soc. 2011 Nov 23;133(46):18574-6. doi: 10.1021/ja2072675. Epub 2011 Nov 1.
Using a combination of periodic, self-consistent, density functional theory (DFT) calculations and CO-stripping voltammetry experiments, we have designed a new class of Pt-M bimetallic monolayer catalysts supported on a non-Pt metal, which exhibit improved stability against CO poisoning and might be suitable for proton-exchange membrane fuel cell anodes. These surfaces help in reducing the overpotential associated with anodic CO oxidation and minimize the amount of Pt used, thereby reducing materials cost. DFT calculations predict highly repulsive interactions between adsorbed CO molecules on these surfaces, leading to weaker binding and lower coverage of CO than on pure Pt, which in turn facilitates oxidative removal of CO from these catalytic surfaces.
我们采用周期性、自洽、密度泛函理论(DFT)计算和 CO 剥离伏安法实验相结合的方法,设计了一类新型的负载在非 Pt 金属上的 Pt-M 双金属单层催化剂,它们对 CO 中毒具有更好的稳定性,可能适用于质子交换膜燃料电池的阳极。这些表面有助于降低与阳极 CO 氧化相关的过电势,并最大限度地减少 Pt 的用量,从而降低材料成本。DFT 计算预测,在这些表面上吸附的 CO 分子之间存在高度排斥的相互作用,导致 CO 的结合较弱,覆盖度较低,低于纯 Pt,这反过来又促进了 CO 从这些催化表面的氧化去除。