pubs.acs.org/Langmuir © 2009 American Chemical Society
Size Effect of Pt Nanoparticle on Catalytic Activity in Oxidation of Methanol and Formic Acid: Comparison to Pt(111), Pt(100), and Polycrystalline Pt Electrodes Choong Kyun Rhee,*,†,‡ Byung-Jun Kim,† Chulho Ham,† Youn-Joong Kim,‡,§ Kyung Song,§ and Kihyun Kwon§ †
Department of Chemistry, Chungnam National University, Daejeon 305-764, South Korea, ‡Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 305-764, South Korea, and § Division of Electron Microscopic Research, Korea Basic Science Institute, Daejeon 305-333, South Korea Received January 17, 2009. Revised Manuscript Received April 6, 2009
This work presents variation of oxidative catalytic activities of methanol and formic acid on Pt nanoparticles of various sizes and a comparison to the results observed on Pt(111), Pt(100), and polycrystalline Pt. The Pt nanoparticles dispersed on platelet carbon nanofiber are cuboctahedral particles, whose sizes span from 5.6 to 1.1 nm. The electrochemically active surface areas, measured using charges of hydrogen adsorption/desorption and stripping of adsorbed CO, are reasonably consistent with those calculated theoretically with a simple cuboctahedron model. However, Pt nanoparticles with extremely small size ( Pt(100) > Pt nanoparticle > Pt(poly) in formic acid oxidation, respectively. Acknowledgment. This study was supported by research grants from the Ministry of Knowledge Economy through the Materials and Component Technology Development Program. The authors thank Professor Seong-Ho Yoon, Kyushu University, Japan, for the kind supply of platelet carbon nanofiber (PCNF) used in this work. Supporting Information Available: Particle size distribution of Pt nanoparticles (Figure S1) and typical chronoamperogram of oxidation of methanol and formic acid on Pt nanoparticle (Figure S2). This material is available free of charge via the Internet at http://pubs.acs.org. DOI: 10.1021/la900204c
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