Ultra-low Pt content PEMFC electrodes have been manufactured using magnetron co-sputtering of carbon and platinum on a commercial E-Tek uncatalyzed gas diffusion layer in plasma fuel cell deposition devices. Pt loadings lower than 0.01 mg cm~(-2) have been realized. The Pt catalyst is dispersed as small clusters with size less than 2 run over a depth of 500 nm. PEMFC test with symmetric electrodes loaded with 0.01 mg cm~(-2) led to maximum reproducible power densities as high as 0.4 Wcm~(-2) with Nafion 212. Replacement of platinum by palladium using plasma sputtering methods was also realized by preparing MEAs composed of 0.01 mg_(Pd) cm~(-2) for the anode and 0.01 mg_(Pd) cm~(-2) + 0.001 mg_(Pt) cm~(-2) for the cathode and Nafion 212 membrane. Power density as high as 250 mW cm~(-2) were achieved at 80°C, which corresponds to a specific power density of 250 kW g_(Pt)~(-1).
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