Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1292465 | Journal of Power Sources | 2006 | 8 Pages |
Abstract
A photographic Pt printing process has been used to prepare catalysts for fuel cell applications. Ferric oxalate was used as a UV sensitizer, absorbing UV energy and converting Fe3+ to Fe2+, which then reduces metal catalyst ions, such as Pt or Pd ions to metals in the presence of a developer, such as ammonium citrate. Transmission electron microscope (TEM) and scanning electron microscope (SEM) studies revealed that Pt particles smaller than 5 nm were formed, however, the particles tended to aggregate and form clusters up to 300 nm. A deposition efficiency of 16% was obtained when Pt was printed on Nafion membranes. The catalytic performance of the photo-printed Pt was evaluated using a single H2 fuel cell. The mass-specific electrochemical area of the catalyst, H2 crossover rate through the Pt-printed membrane and the membrane resistance were measured. At 60 °C, a peak power density of 75 mW cmâ2 was obtained with a MEA consisting of photo-printed Pt (0.12 mg cmâ2) on a Nafion membrane as the catalyst. Cyclic voltammetry measurements in solutions containing methanol or formic acid showed that a mass-specific methanol oxidation current of 197 mA mgâ1 Pt could be achieved and that the co-deposition of Pd with Pt lowered the formic acid oxidation potential in addition to reducing the formation of the “poisonous” intermediate COads.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Juan Jiang, Timothy D. Hall, Loukas Tsagalas, Davide A. Hill, Albert E. Miller,