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Size Effects on Reactivity of Pt Nanoparticles in CO Monolayer Oxidation: The Role of Surface Mobility Full article

Conference Nanoparticle Assemblies: RSC Faraday Discussion 125
14-16 Jul 2003 , Liverpool
Source Faraday Discussion 125: Nanoparticle Assemblies, July 13-16, 2003, Liverpool, UK
Compilation, 2003.
Journal Faraday Discussions
ISSN: 1359-6640 , E-ISSN: 1364-5498
Output data Year: 2004, Volume: 125, Pages: 357-377 Pages count : 21 DOI: 10.1039/b303911k
Authors Maillard F. 1 , Eikerling M. 1 , Cherstiouk O.V. 1,2 , Schreier S. 1 , Savinova E. 1,2 , Stimming U. 1
Affiliations
1 Department of Physics E19, Technische Universität München, D-85748, Garching, Germany
2 Boreskov Institute of Catalysis SB RAS, Novosibirsk 630090, Russia

Funding (2)

1 German Research Foundation Sti 74-8-3
2 German Research Foundation Sti 74-8-4

Abstract: In the present paper we study the reactivity of model Pt nanoparticles supported on glassy carbon. The particle size effect is rationalized for CO monolayer oxidation exploring electrochemical methods (stripping voltammetry and chronoamperometry) and modelling. Significant size effects are observed in the particle size interval from ca. 1 to 4 nm, including the positive shift of the CO stripping peak with decreasing particle size and a pronounced asymmetry of the current transients at constant potential. The latter go through a maximum at low COads conversion and exhibit tailing, which is the longer the smaller the particle size. Neither mean field nor nucleation & growth models give a coherent explanation of these experimental findings. We, therefore, suggest a basic model employing the active site concept. With a number of reasonable simplifications a full analytical solution is obtained, which allows a straightforward comparison of the theory with the experimental data. A good correspondence between experiment and theory is demonstrated. The model suggests restricted COads mobility at Pt nanoparticles below ca. 2 nm size, with the diffusion coefficient strongly dependent on the particle size, and indicates a transition towards fast diffusion when the particle size exceeds ca. 3 nm. Estimates of relevant kinetic parameters, including diffusion coefficient, reaction constant etc. are obtained and compared to the literature data for extended Pt surfaces.
Cite: Maillard F. , Eikerling M. , Cherstiouk O.V. , Schreier S. , Savinova E. , Stimming U.
Size Effects on Reactivity of Pt Nanoparticles in CO Monolayer Oxidation: The Role of Surface Mobility
In compilation Faraday Discussion 125: Nanoparticle Assemblies, July 13-16, 2003, Liverpool, UK. 2004. – C.357-377. DOI: 10.1039/b303911k WOS Scopus РИНЦ ANCAN OpenAlex
Dates:
Submitted: Apr 8, 2003
Accepted: May 1, 2003
Published online: Sep 30, 2003
Identifiers:
Web of science: WOS:000188238900024
Scopus: 2-s2.0-1542411495
Elibrary: 13455010
Chemical Abstracts: 2003:933538
Chemical Abstracts (print): 140:345588
OpenAlex: W2137485657
Citing:
DB Citing
Web of science 371
Scopus 406
Elibrary 400
OpenAlex 412
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