Enhanced Oxygen Reduction Activity on Pt/C for Nafion-free, Thin, Uniform Films in Rotating Disk Electrode Studies

Journal Article · Tue Jan 01 00:00:00 EST 2013 · ECS Transactions

DOI:https://doi.org/10.1149/05801.0015ecst· OSTI ID:1136225

Shinozaki, Kazuma ^[1]; Pivovar, Bryan S. ^[2]; Kocha, Shyam S. ^[2]

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1. Toyota Central R&D Labs., Inc., Aichi (Japan); Colorado School of Mines, Golden, CO (United States)
2. National Renewable Energy Lab. (NREL), Golden, CO (United States)

Commercially available nanoparticle platinum on high surface area carbon black (Pt/HSC) electrocatalysts were characterized in rotating disk electrode (RDE) setups using varying ink formulations and film drying techniques in an attempt to obtain thin, uniform films and reproducible activity. Electrodes prepared from Nafion-free inks that were dried under an isopropyl alcohol (IPA) atmosphere produced uniform, thin films at low electrocatalyst loadings of ~4.5 mg/cm² Pt. These Nafion-free/IPA-dried electrodes were found to exhibit oxygen reduction reaction (ORR) activities higher than conventional Nafion-based/Air-dried electrodes by a factor of ~2.8. The magnitude of mass and specific activities were determined to be i_m ~771 ±56 mA/mgPt and i_s~812 ±59 mA/cm²Pt respectively and appear to be the highest values reported for RDE measurements on Pt/HSC in 0.1M HClO₄ at 20 mV/s and 25°C. Electrochemical diagnostics including ORR I-V profiles, cyclic voltammograms and electrochemical impedance spectroscopy (EIS) studies were conducted to investigate the thin film Pt/HSC electrodes and correlate results to film morphology and electrochemical activity.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Transportation Office. Fuel Cell Technologies Office
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 1136225
• Journal Information: ECS Transactions, Vol. 58, Issue 1, 2013; ISSN 1938-5862
• Country of Publication: United States
• Language: English

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