Electrocatalysis, particle size effects

Cherstiouk OV, Simonov PA, Savinova ER. 2003a. Model approach to evaluate particle size effects in electrocatalysis Preparation and properties of Pt nanoparticles supported on GC and HOPG. Electrochim Acta 48 3851-3860. 

Guerin S, Hayden BE, Pletcher D, Rendall ME, Suchsland J-P, WiUiams LJ. 2006b. Combinatorial approach to the study of particle size effects in electrocatalysis synthesis of supported gold nanoparticles. J Comb Chem 8 791-798. 

Mayrhofer KJJ, Blizanac BB, Arenz M, Stamenkovic VR, Ross PN, Markovic NM. 2005b. The impact of geometric and surface electronic properties of Pt-catalysts on the particle size effect in electrocatalysis. J Phys Chem B 109 14433-14440. 

The role of particle size in catalysis and electrocatalysis is a subject of longstanding interest. It is not our intention here to discuss in detail the available experimental and theoretical literature. Extensive reviews on particle-size effects in gas-phase catalysis and electrocatalysis can be found in the papers of Henry [25] and Kinoshita [26], respectively. Also, several monographs, reviews, and conference proceedings discuss particle-size effects from experimental, theoretical, and computational points of view [9,27,28]. 

When the catalytic properties of supported clusters are measured by standard electrochemical methods such as cyclic voltammetry or oxidation transient measurement, only the average properties of the entire distribution of active particles on the electrode surface can be measured. A range of properties of supported nanoparticles, e.g., their geometric structure, their electronic and magnetic properties, as well as their catalytic activity, depends on the size of the particles. Geometric as well as electronic effects have been used to explain particle-size effects in electrocatalysis. 

Designing alloy electrocatalysts by the so-called ad-atom method, and by alloy sputtering for oxidation of CH3OH and CO, and for CO tolerance in H2 oxidation, respectively, as well as for O2 reduction are discussed. Many years of experience are summarized and collaborations with other groups are highlighted. The particle size effect in electrocatalysis by small particle electrodes, and the effect of corrosion of carbon-black supported nanoparticles on the electrocatalytic activity are also discussed. All these factors, as well as catalyst lifetimes, are very important in fuel cell performance and in the final cost estimates for the practical fuel cell applications. 

The intrinsic exchange current density,/ , is not a mere materials constant, but it depends on size distributions of catalyst nanoparticles, their surface structure, as well as surface composition in the case of alloy catalysts like PtRu. In this section, we discuss modeling approaches that highlight particle size effects and the role of surface heterogeneity in fuel cell electrocatalysis. 

Shao MH, Peles A, Shoemaker K (2011) Electrocatalysis on platinum nanoparticles particle size effect on oxygen reduction reaction activity. Nano Lett 11(9) 3714—3719... 

Hayden BE, Suchsland J-P (2009) Support and particle size effects in electrocatalysis. In Koper MTM (ed) Fuel cell catalysis a surface science approach. Wiley, Hoboken, NJ, pp 567-592... 

Hayden, B. E. and J. Suchsland. 2009. Support and Particle Size Effects in Electrocatalysis, in Fuel Cell Catalysis—A Surface Science Approach, editor, M. T. M. Koper, 567-592. Hoboken, New Jersey John Wiley Sons. 

Mukeijee S, McBreen J. 1989. Effect of particle size on the electrocatalysis by carbon-supported Pt electrocatalysts an in situ XAS investigation. J Electroanal Chem 448 163-171. 

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