Formic Acid Oxidation on Bi-modified Pt Nanoparticles of Various Sizes

Bulletin of the Korean chemical society

Tae Hoon Lim¹  Ting Zhang¹  Choong Kyun Rhee¹  Byung Jun Kim¹  Jandee Kim¹  Changhoon Jung¹ 

关键词: Bismuth;    Platinum nanoparticle;    Size effect;    Formic acid oxidation;    Catalytic poison;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

This work presents oxidation of formic acid on Bi-modified Pt nanoparticles of various sizes. The sizes of the studied Pt nanoparticles range from 1.5 to 5.6 nm (detailed in Rhee, C. K.; Kim, B.-J.; Ham, C.; Kim, Y.-J.; Song, K.; Kwon, K. Langmuir 2009, 25, 7140-7147), and the surfaces of the Pt nanoparticles are modified with irreversibly adsorbed Bi. The investigated coverages of Bi on the Pt nanoparticles are 0.12 and 0.25 as determined by coulometry of the oxidation of adsorbed hydrogen and Bi, and X-ray photoelectron spectroscopy. The cyclic voltammetric behavior of formic acid oxidation reveals that the adsorbed Bi enhances the catalytic activity of Pt nanoparticles by impeding a poison-forming dehydration path with a concomitant promotion of a dehydrogenation path. The chronoamperometric results indicate that elemental Bi and partially oxidized Bi are responsible for the catalytic enhancement, when the Bi coverages on Pt nanoparticles are 0.12 and 0.25, respectively. The size effect of Bi-modified Pt nanoparticles in formic acid oxidation is discussed in terms of specific activity (current per unit surface area) and mass activity (current per unit mass).

【 授权许可】

Unknown