Journal of Power Sources, Vol.208, 257-262, 2012
Fundamental studies on direct ammonia fuel cell employing anion exchange membrane
The fundamental characteristics of direct ammonia fuel cell employing anion exchange membrane (AEM) as an electrolyte was evaluated. The fuel cells with three different anodes of Pt/C, Pt-Ru/C, and Ru/C were applied for the performance tests. The open circuit voltage (OCV) was notably lower than the ideal electromotive force of 1.17 V and significantly dependent on the electrocatalysts. The OCV achieved was in the following sequence: Pt-Ru/C> Pt/C > Ru/C. Furthermore, the ammonia permeated through the AEM by the solubility-diffusion mechanism and the formation of oxidants such as N-2 and NO was detected in the cathode exhaust gas. This result indicates the oxidation of ammonia in the cathode, which will be another factor for the reduction in OCV. Note that OCV and performance continuously decreased during the consecutive I-V characteristic measurements because of the N-ad poisoning over the surface of anode catalysts. (C) 2012 Elsevier B.V. All rights reserved.
Keywords:Anion exchange membrane;Direct ammonia fuel cell;Electrocatalyst;Ammonia oxidation;Atomic nitrogen adspecies