Development of Palladium and Platinum based Membrane Electrode Assemblies and Performance Characterization in the Alkaline Direct Ethanol Fuel Cell

Alkaline direct ethanol fuel cells (ADEFCs) have gained much attention in the last years due to their use of alternative energy sources. Commercial carbon supported palladium and platinum catalysts were ex-situ characterized by means of cyclic voltammetry experiments for their application in ADEFCs. The activity for the ethanol oxidation reaction (EOR) of the Pd/C catalyst was analyzed and an electrochemical active surface area (ECSA) of 411 cm2 mg-1, an onset potential of 0.255 V and a maximum current density for the forward scan of 126 mA cm-2 was examined. In addition, the performance of the Pt/C catalyst for the oxygen reduction reaction (ORR) was investigated resulting in an onset potential of 0.95 V and a limiting current density of ‑3.68 mA cm‑2 at 2000 rpm. Moreover, in-situ characterization in a self-designed ADEFC was performed. Therefore, a membrane electrode assembly (MEA) was developed using the Pt/C catalyst as active cathode material, Pd/C as active anode material and a commercial fumasep® FAA-3-PK-130 as anion-exchange membrane. The results of the single cell tests showed that a humidified oxygen flow rate of 20 mL min-1 and an ethanol fuel flow rate of 200 mL min-1 are most optimal for a good performance of the fuel cell. A maximum power density of 0.4 mW cm-2 was achieved.