Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
J Am Chem Soc. 2010 Nov 17;132(45):16127-33. doi: 10.1021/ja106389k. Epub 2010 Oct 27.
The role of alkali cations (Li(+), Na(+), K(+), Cs(+), and Be(2+)) on the blank voltammetric response and the oxidative stripping of carbon monoxide from stepped Pt single-crystal electrodes in alkaline media has been investigated by cyclic voltammetry. A strong influence of the nature of the cation on both the blank voltammetric profile and the CO oxidation is observed and related to the influence of the cation on the specific adsorption of OH on the platinum surface. Especially Li(+) and Be(2+) cations markedly affect the adsorption of OH and thereby have a significant promoting effect on CO(ads) oxidation. The voltammetric experiments suggest that, on Pt(111), the influence of Li(+) (and Be(2+)) is primarily through a weakening of the repulsive interactions between the OH in the OH adlayer, whereas in the presence of steps also, the onset of OH adsorption is at a lower potential, both on steps and on terraces.
碱金属阳离子（Li(+)、Na(+)、K(+)、Cs(+) 和 Be(2+)）对碱性介质中阶梯状 Pt 单晶电极上一氧化碳的空白伏安响应和氧化剥离的影响通过循环伏安法进行了研究。阳离子的性质对空白伏安曲线和 CO 氧化的影响都很强，并与阳离子对 OH 在铂表面的特殊吸附的影响有关。特别是 Li(+)和 Be(2+)阳离子显著影响 OH 的吸附，从而对 CO(ads)氧化有显著的促进作用。伏安实验表明，在 Pt(111)上，Li(+)（和 Be(2+)）的影响主要是通过削弱 OH 在 OH 吸附层之间的排斥相互作用，而在存在台阶的情况下，OH 的吸附起始电位也更低，无论是在台阶上还是在平台上。
