Crystallite size effects of carbon-supported platinum on oxygen reduction in liquid acids

Govindasamy Tamizhmani, J. P. Dodelet, D. Guay

Research output: Contribution to journalArticle

108 Citations (Scopus)

Abstract

Pt/C catalysts with two different Pt crystallite sizes [as-received (20 weight percent (w/o) Pt/C powder from E-TEK) and heat-treated (900°C in inert atmosphere)] were analyzed for the reduction of oxygen in half-cells using rotating disk electrodes. Measurements in HF (1.17 M) show that the specific activity of the catalysts increases with the Pt crystallite size. In contrast, measurements in H2SO4 (1.17 M) indicate that the specific activity is nearly independent of the Pt crystallite size. One of the reasons for the difference in behavior observed between these acids is the difference in specific adsorption of anions on the Pt sites from H2SO4 (adsorbing) and HF (nonadsorbing) solutions. This study indicates that 1 both the oxygen reduction reaction and anion adsorption on the Pt sites are crystallite-size sensitive in H2SO4 solution. In solid polymer fuel cells (SPFCs), the anions are anchored on the backbone of the polymer matrix, and hence only a minimal anion adsorption is expected on the Pt sites of gas diffusion electrodes. From results of the present study, it is believed that the Pt/membrane interface in SPFCs could be better mimicked by the Pt/HF interface rather than the Pt/H2SO4 interface.

Original languageEnglish (US)
Pages (from-to)18-23
Number of pages6
JournalJournal of the Electrochemical Society
Volume143
Issue number1
StatePublished - Jan 1996
Externally publishedYes

Fingerprint

Crystallite size
Platinum
Anions
platinum
Negative ions
Carbon
Oxygen
anions
acids
Acids
carbon
Liquids
oxygen
liquids
Adsorption
fuel cells
adsorption
Fuel cells
Polymers
polymers

ASJC Scopus subject areas

  • Electrochemistry
  • Surfaces, Coatings and Films
  • Surfaces and Interfaces

Cite this

Crystallite size effects of carbon-supported platinum on oxygen reduction in liquid acids. / Tamizhmani, Govindasamy; Dodelet, J. P.; Guay, D.

In: Journal of the Electrochemical Society, Vol. 143, No. 1, 01.1996, p. 18-23.

Research output: Contribution to journalArticle

@article{df136ce127b0437fa55dc84268ac2bd0,
title = "Crystallite size effects of carbon-supported platinum on oxygen reduction in liquid acids",
abstract = "Pt/C catalysts with two different Pt crystallite sizes [as-received (20 weight percent (w/o) Pt/C powder from E-TEK) and heat-treated (900°C in inert atmosphere)] were analyzed for the reduction of oxygen in half-cells using rotating disk electrodes. Measurements in HF (1.17 M) show that the specific activity of the catalysts increases with the Pt crystallite size. In contrast, measurements in H2SO4 (1.17 M) indicate that the specific activity is nearly independent of the Pt crystallite size. One of the reasons for the difference in behavior observed between these acids is the difference in specific adsorption of anions on the Pt sites from H2SO4 (adsorbing) and HF (nonadsorbing) solutions. This study indicates that 1 both the oxygen reduction reaction and anion adsorption on the Pt sites are crystallite-size sensitive in H2SO4 solution. In solid polymer fuel cells (SPFCs), the anions are anchored on the backbone of the polymer matrix, and hence only a minimal anion adsorption is expected on the Pt sites of gas diffusion electrodes. From results of the present study, it is believed that the Pt/membrane interface in SPFCs could be better mimicked by the Pt/HF interface rather than the Pt/H2SO4 interface.",
author = "Govindasamy Tamizhmani and Dodelet, {J. P.} and D. Guay",
year = "1996",
month = "1",
language = "English (US)",
volume = "143",
pages = "18--23",
journal = "Journal of the Electrochemical Society",
issn = "0013-4651",
publisher = "Electrochemical Society, Inc.",
number = "1",

}

TY - JOUR

T1 - Crystallite size effects of carbon-supported platinum on oxygen reduction in liquid acids

AU - Tamizhmani, Govindasamy

AU - Dodelet, J. P.

AU - Guay, D.

PY - 1996/1

Y1 - 1996/1

N2 - Pt/C catalysts with two different Pt crystallite sizes [as-received (20 weight percent (w/o) Pt/C powder from E-TEK) and heat-treated (900°C in inert atmosphere)] were analyzed for the reduction of oxygen in half-cells using rotating disk electrodes. Measurements in HF (1.17 M) show that the specific activity of the catalysts increases with the Pt crystallite size. In contrast, measurements in H2SO4 (1.17 M) indicate that the specific activity is nearly independent of the Pt crystallite size. One of the reasons for the difference in behavior observed between these acids is the difference in specific adsorption of anions on the Pt sites from H2SO4 (adsorbing) and HF (nonadsorbing) solutions. This study indicates that 1 both the oxygen reduction reaction and anion adsorption on the Pt sites are crystallite-size sensitive in H2SO4 solution. In solid polymer fuel cells (SPFCs), the anions are anchored on the backbone of the polymer matrix, and hence only a minimal anion adsorption is expected on the Pt sites of gas diffusion electrodes. From results of the present study, it is believed that the Pt/membrane interface in SPFCs could be better mimicked by the Pt/HF interface rather than the Pt/H2SO4 interface.

AB - Pt/C catalysts with two different Pt crystallite sizes [as-received (20 weight percent (w/o) Pt/C powder from E-TEK) and heat-treated (900°C in inert atmosphere)] were analyzed for the reduction of oxygen in half-cells using rotating disk electrodes. Measurements in HF (1.17 M) show that the specific activity of the catalysts increases with the Pt crystallite size. In contrast, measurements in H2SO4 (1.17 M) indicate that the specific activity is nearly independent of the Pt crystallite size. One of the reasons for the difference in behavior observed between these acids is the difference in specific adsorption of anions on the Pt sites from H2SO4 (adsorbing) and HF (nonadsorbing) solutions. This study indicates that 1 both the oxygen reduction reaction and anion adsorption on the Pt sites are crystallite-size sensitive in H2SO4 solution. In solid polymer fuel cells (SPFCs), the anions are anchored on the backbone of the polymer matrix, and hence only a minimal anion adsorption is expected on the Pt sites of gas diffusion electrodes. From results of the present study, it is believed that the Pt/membrane interface in SPFCs could be better mimicked by the Pt/HF interface rather than the Pt/H2SO4 interface.

UR - http://www.scopus.com/inward/record.url?scp=0029754613&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029754613&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0029754613

VL - 143

SP - 18

EP - 23

JO - Journal of the Electrochemical Society

JF - Journal of the Electrochemical Society

SN - 0013-4651

IS - 1

ER -