Kim, Jae Hong Jo, Yoo Yeon Cho, Eun Ae Jang, Jong Hyun Kim, Hyoung Juhn Lim, Tae-Hoon Oh, In-Hwan Ko, Jae Jun Son, Ik Jae 2024-01-20T19:30:41Z 2024-01-20T19:30:41Z 2021-09-05 2010-05 0013-4651 https://pubs.kist.re.kr/handle/201004/131473 This paper uses a variety of physicochemical methods to elucidate the mechanism by which cathode inlet relative humidity (RH) degrades a proton exchange membrane fuel cell (PEMFC) during startup-shutdown cycling. The results revealed that the pronounced Pt coarsening (agglomeration)/oxidation/dissolution (detachment) and migration were observed along with corrosion of the carbon support at the majority of cathode catalyst layers when PEMFCs were exposed to a higher cathode inlet RH during 1500 startup-shutdown cycles. These changes contributed to the significant loss of Pt mass available for electrochemical reactions and an active Pt surface area at the cathode, thus decaying the performance of the fuel cell. In addition, the rate of these multiple processes was RH-dependent. However, the degradation at the anode and membrane was not as severe as those observed at the cathode and did not show any dependence on the cathode inlet RH. Based on these results, a modified mechanism for the degradation of the cathode catalyst layer during startup-shutdown cycling of PEMFCs is proposed to explain the effects of RH on fuel cell performance and durability. English ELECTROCHEMICAL SOC INC MEMBRANE-ELECTRODE ASSEMBLIES ELECTROCATALYST MICROSTRUCTURE NANOPARTICLES PERFORMANCE DISSOLUTION CATALYSTS ISSUES Effects of Cathode Inlet Relative Humidity on PEMFC Durability during Startup-Shutdown Cycling Article 10.1149/1.3327888 1 JOURNAL OF THE ELECTROCHEMICAL SOCIETY, v.157, no.5, pp.B633 - B642 JOURNAL OF THE ELECTROCHEMICAL SOCIETY 157 5 B633 B642 scie scopus 000276555300015 2-s2.0-77951177031 Electrochemistry Materials Science, Coatings & Films Electrochemistry Materials Science Article MEMBRANE-ELECTRODE ASSEMBLIES ELECTROCATALYST MICROSTRUCTURE NANOPARTICLES PERFORMANCE DISSOLUTION CATALYSTS ISSUES carbon corrosion dissolving electrochemical electrodes oxidation platinum proton exchange membrane fuel cells