TY - JOUR
T1 - Effects of the decomposition products of sulfonated polyimide and Nafion membranes on the degradation and recovery of electrode performance in PEFCs
AU - Kabasawa, Akihiro
AU - Saito, Jumpei
AU - Miyatake, Kenji
AU - Uchida, Hiroyuki
AU - Watanabe, Masahiro
N1 - Funding Information:
This work was partly supported by a grant from the fund for “Leading Project: Next Generation Fuel Cells” and a Grant-in-Aid for Scientific Research (20350086) of the Ministry of Education, Science, Culture, Sports and Technology of Japan. The authors thank Prof. Donald A. Tryk of the Fuel Cell Nanomaterials Center (University of Yamanashi) for his kind advice. The authors thank Mr. Hirotaka Suda and Mr. Naohiko Sawatari of Fuji Electric Advanced Technology for their contribution in performing the ion chromatography analysis. The authors also thank JEOL for their contribution in performing the IC/MS analysis.
PY - 2009/4/1
Y1 - 2009/4/1
N2 - Degradation and recovery of electrode performance during the operation of polymer electrolyte fuel cells (PEFCs) with sulfonated polyimide (SPI-8) and Nafion® membranes were evaluated by changes in cell voltage (Ecell), mass activity (MA), Tafel slope (TS), and electrochemical surface area (ECA) of the Pt catalyst. During continuous cell operation, values of Ecell, MA and ECA decreased, but TS increased. It was found by ion chromatography combined with mass spectrometry (IC/MS) that the drain water contained, as decomposition products, bisulfate and several other ionic compounds derived from the side chain of SPI-8. These ionic compounds were found to adsorb on the surface of the Pt cathode catalyst and to suppress oxygen adsorption, resulting in increases in the overpotential for the oxygen reduction reaction (ORR). The cathode performance was able to recover by potential cycling under high humidity conditions, as the ionic compounds were removed from the Pt surface.
AB - Degradation and recovery of electrode performance during the operation of polymer electrolyte fuel cells (PEFCs) with sulfonated polyimide (SPI-8) and Nafion® membranes were evaluated by changes in cell voltage (Ecell), mass activity (MA), Tafel slope (TS), and electrochemical surface area (ECA) of the Pt catalyst. During continuous cell operation, values of Ecell, MA and ECA decreased, but TS increased. It was found by ion chromatography combined with mass spectrometry (IC/MS) that the drain water contained, as decomposition products, bisulfate and several other ionic compounds derived from the side chain of SPI-8. These ionic compounds were found to adsorb on the surface of the Pt cathode catalyst and to suppress oxygen adsorption, resulting in increases in the overpotential for the oxygen reduction reaction (ORR). The cathode performance was able to recover by potential cycling under high humidity conditions, as the ionic compounds were removed from the Pt surface.
KW - Degradation and recovery
KW - Electrolyte decomposition
KW - Impurity adsorption
KW - PEFC
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U2 - 10.1016/j.electacta.2008.11.036
DO - 10.1016/j.electacta.2008.11.036
M3 - Article
AN - SCOPUS:61449174773
SN - 0013-4686
VL - 54
SP - 2754
EP - 2760
JO - Electrochimica Acta
JF - Electrochimica Acta
IS - 10
ER -