Preparation of platinum-based catalysts for fuel cell using a supercritical fluid deposition method: Effects of reaction parameters

Pt-based catalysts deposited on the surface of a gas diffusion electrode were prepared using a supercritical fluid deposition method. The metallic precursor, platinum (II) acetylacetonate (Pt(II)(acac) ₂ , was first dissolved in supercritical CO ₂ (scCO ₂ ) and impregnated onto the carbon particles supported by carbon paper (uncatalyzed gas diffusion electrodes) with a projected active area of 5 cm ² . The effects of reaction parameters (reduction temperature, time, and addition of methanol) on metal loading and dispersion on substrate were evaluated according to the surface analysis techniques. Impregnation of Pt(acac) ₂ into carbon paper in the scCO ₂ indicates that metal compactness on substrate is correlated with impregnation time, while Pt aggregation increased along with the thermal reduction time and temperature. This is an abstract of a paper presented at the 106th AWMA Annual Conference and Exhibition (Chicago, IL 6/25-28/2013).