Particle size effect of carbon-supported platinum catalysts for the electrooxidation of methanol

doi:10.1016/0022-0728(94)03648-M

Journal of Electroanalytical Chemistry

Volume 382, Issues 1–2, 7 February 1995, Pages 65-72

https://doi.org/10.1016/0022-0728(94)03648-M Get rights and content

Abstract

The effect of the particle size of carbon-supported Pt catalysts on the electrooxidation of methanol was studied. Different methods were used to prepare $Pt C$ catalysts with particle sizes ranging between 1.2 and 10 nm. The possible interaction of Pt with carbon surface groups was also investigated by preparing catalysts on oxidized and non-oxidized carbon supports. The specific activity was found to decrease with decreasing particle size in the range 4.5–1.2 nm. Carbon-supported Pt particles appear to be more active than non-supported particles and the presence of an acidic group on the support slightly enhances this effect. The dependence of the activity on the particle size can be explained in terms of either its effect on the formation of an adsorbed hydroxy species or its effect on the number of methanol adsorption sites.

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Citation Excerpt :
In addition, the mean size of Pt nanoparticles in these surface-unmodified carbon supports is quite large, in the range of 5.8–12.6 nm, which is harmful for the performance [32]. The normally modification methods used such as by strong acid or oxidant oxidation [33], covalent grafting [34], π—π interaction [35]. However, these methods usually accompany complicated treatments and inevitably damages on the structural, mechanical, and electrical properties [32,36].
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Regular paperParticle size effect of carbon-supported platinum catalysts for the electrooxidation of methanol

Abstract

J. Electroanal. Chem.

J. Electroanal. Chem.

J. Electroanal. Chem.

Electrochim. Acta

J. Electron Spectrosc. Relat. Phenom

Electrochim. Acta

J. Electroanal Chem.

Electrochim. Acta

J. Electroanal. Chem.

J. Electroanal Chem.

J. Electroanal. Chem.

Regular paper
Particle size effect of carbon-supported platinum catalysts for the electrooxidation of methanol