Improving the Energy Efficiency of Direct Formate Fuel Cells with a Pd/C-CeO2 Anode Catalyst and Anion Exchange Ionomer in the Catalyst Layer

Abstract

This article describes the development of a high power density Direct Formate Fuel Cell (DFFC) fed with potassium formate (KCOOH). The membrane electrode assembly (MEA) contains no platinum metal. The cathode catalyst is FeCo/C combined with a commercial anion exchange membrane (AEM). To enhance the power output and energy efficiency we have employed a nanostructured Pd/C-CeO 2 anode catalyst. The activity for the formate oxidation reaction (FOR) is enhanced when compared to a Pd/C catalyst with the same Pd loading. Fuel cell tests at 60 • C show a peak power density of almost 250 mW cm −2 . The discharge energy (14 kJ), faradic efficiency (89%) and energy efficiency (46%) were determined for a single fuel charge (30 mL of 4 M KCOOH and 4 M KOH). Energy analysis demonstrates that removal of the expensive KOH electrolyte is essential for the future development of these devices. To compensate we apply for the first time a polymeric ionomer in the catalyst layer of the anode electrode. A homopolymer is synthesized by the radical polymerization of vinyl benzene chloride followed by amination with 1,4-diazabicyclo[2.2.2]octane (DABCO). The energy delivered, energy efficiency and fuel consumption efficiency of DFFCs fed with 4 M KCOOH are doubled with the use of the ionomer.

Alkaline membrane fuel cells: anion exchange membranes and fuels

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Utilizing Formate as an Energy Carrier by Coupling CO2 Electrolysis with Fuel Cell Devices

“…The transport of OH − from the cathode to the anode compartment maintains the charge neutrality during operation. The theoretical cell voltage is 1.45 V (pH 14) , the highest among all common fuel cell systems.…”

Electro-oxidation competency of palladium nanocatalysts over ceria–carbon composite supports during alkaline ethylene glycol oxidation

“…37 Palladium particles deposited on carbon-ceria conductive support was used by Miller et al to study hydrogen oxidation reaction in alkaline medium [38][39] and to test direct formate fuel cell performance. 40 However, to the best of our knowledge, a systematic study on the variation in electrooxidation performance of Pd in alkaline medium…”