Electrochemical Evaluation of Non-Precious Metal Catalysts for Fuel Cell Applications

Proton exchange membrane fuel cell (PEMFC) and anion exchange membrane fuel cells (AEMFCs) are devices that generate electricity by means of a chemical reaction. Both PEMFCs and AEMFCs provide an environmentally friendly alternative to oil-derived fuels with higher efficiency than that of the combustion engine. They can be used to power cars, and for other portable applications. However, one of the major disadvantages of PEMFCs and AEMFCs is the high cost associated with using platinum group metals (PGMs) as the catalyst for the reactions taking place on both the anode and cathode electrodes. Replacing platinum at the cathode and anode electrodes with non-precious group metal (NPGM) catalysts would significantly decrease the cost of fuel cells. The purpose of our research is to determine the optimal parameters affecting the catalytic performance of NPGM catalyst for the oxygen reduction reaction (ORR) taking place at the cathode. We synthesized NPGM catalysts using various Cu and Fe salts, nitrogen precursors (rich sources) along with a carbon support. The as prepared catalyst show very low ORR activity, but after thermal activation under inert atmosphere the catalytic activity was significantly improved. Electrochemical activity was measured by the rotating ring disk electrode (RRDE) technique in both alkaline and acidic electrolytes. The iron sulfate catalyst heat-treated at 900 ^oC showed the best catalytic activity in acidic and alkaline environments. The iron sulfate catalyst performance was tested in both PEM and AEM fuel cell.