Park, Ji-Yeon Scibioh, M. Aulice Kim, Soo-Kil Kim, Hyoung-Juhn Oh, In-Hwan Lee, Tai Gyu Ha, Heung Yong 2024-01-20T22:01:57Z 2024-01-20T22:01:57Z 2021-09-03 2009-02 0360-3199 https://pubs.kist.re.kr/handle/201004/132765 This paper addresses a gradual performance loss that is encountered in a direct methanol fuel cell (DMFC) when it is subjected to a continuous operation at constant-load conditions for a period of 600 h. To gain insights into the physico-chemical origins of the degradation process, various analytical techniques are employed and characterization of the membrane electrode assembly (MEA) is carried out before and after the lifetime test. The results reveal that the performance degradation of MEA mainly stems from the degradations at the cathode and this is further confirmed by individual impedance analyses of cathode and, anode as well as by the observation on finding increased quantity of methanol exiting from the cathode with increased operational time. Supplement experiments with the cathodes containing either pre-oxidized Pt catalyst or a fractional amount of Ru catalyst offer new clues to understand the deactivation mechanism. The hydrophobicity losses of gas diffusion layers are prominent in the outlet regions compared to the inlet regions of the DMFC assembly. Further, a couple of restoration techniques are employed to evaluate performance recovery. A periodical on-off switching of applied load and an air-break technique are found to be effective to restore the performance loss that occurs during fuel cell operations. (c) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved. English PERGAMON-ELSEVIER SCIENCE LTD PT/C CATALYSTS CATHODE OPERATION DMFC CROSSOVER BLACK PEFC CV Investigations of performance degradation and mitigation strategies in direct methanol fuel cells Article 10.1016/j.ijhydene.2008.10.092 1 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, v.34, no.4, pp.2043 - 2051 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 34 4 2043 2051 scie scopus 000264355300049 2-s2.0-59649104097 Chemistry, Physical Electrochemistry Energy & Fuels Chemistry Electrochemistry Energy & Fuels Article PT/C CATALYSTS CATHODE OPERATION DMFC CROSSOVER BLACK PEFC CV Direct methanol fuel cell Lifetime operation Performance loss Durability Hydrophobicity Recovery process