TY - JOUR
T1 - Performance hysteresis phenomena of anion exchange membrane fuel cells using an Fe–N–C cathode catalyst and an in-house-developed polymer electrolyte
AU - Otsuji, Kanji
AU - Yokota, Naoki
AU - Tryk, Donald A.
AU - Kakinuma, Katsuyoshi
AU - Miyatake, Kenji
AU - Uchida, Makoto
N1 - Funding Information:
This project was partly supported by the New Energy and Industrial Technology Development Organization (NEDO) Japan through funds for the “Advanced Research Program for Energy and Environmental Technologies,” by the Japan Society for the Promotion of Science (JSPS) and the Swiss National Science Foundation (SNSF) under the Joint Research Projects (JRPs) program, and by the Japan Science and Technology (JST) through Strategic International Collaborative Research Program (SICORP) .
Publisher Copyright:
© 2020 The Authors
PY - 2021/3/1
Y1 - 2021/3/1
N2 - We focus on the water management challenges and report on the improvements of cell performance for anion exchange membrane fuel cells (AEMFCs) using a non-PGM catalyst (Fe–N–C) for the cathode and an in-house-developed anion exchange ionomer (quaternized poly(arylene perfluoroalkylene), QPAF-4) for both the membrane and the catalyst layers (CLs) binder under practical gas flow rates conditions. The cell using the Fe–N–C cathode exhibited similar current-voltage (I–V) performance compared with those using Pt catalyst supported on carbon black. The cell using the Fe–N–C catalyst showed I–V hysteresis between increasing and decreasing current. The hysteresis decreased with increasing back-pressure. Based on the results of various I–V measurements, we conclude that the hysteresis is related to water supplied to the cathode using the Fe–N–C catalyst. Tafel slope component analysis revealed that a severe polarization occurred, amounting to slope octupling, with increasing current density, most likely due to the addition of water transport to the usual combination of gas and ionic transport. This severe polarization was alleviated after the cathode layer became sufficiently hydrated. We found from these results that water management is essential, due to the role of water as a reactant in the cathode reaction, for high-performance AEMFCs.
AB - We focus on the water management challenges and report on the improvements of cell performance for anion exchange membrane fuel cells (AEMFCs) using a non-PGM catalyst (Fe–N–C) for the cathode and an in-house-developed anion exchange ionomer (quaternized poly(arylene perfluoroalkylene), QPAF-4) for both the membrane and the catalyst layers (CLs) binder under practical gas flow rates conditions. The cell using the Fe–N–C cathode exhibited similar current-voltage (I–V) performance compared with those using Pt catalyst supported on carbon black. The cell using the Fe–N–C catalyst showed I–V hysteresis between increasing and decreasing current. The hysteresis decreased with increasing back-pressure. Based on the results of various I–V measurements, we conclude that the hysteresis is related to water supplied to the cathode using the Fe–N–C catalyst. Tafel slope component analysis revealed that a severe polarization occurred, amounting to slope octupling, with increasing current density, most likely due to the addition of water transport to the usual combination of gas and ionic transport. This severe polarization was alleviated after the cathode layer became sufficiently hydrated. We found from these results that water management is essential, due to the role of water as a reactant in the cathode reaction, for high-performance AEMFCs.
KW - Anion exchange membrane fuel cell
KW - Catalyst layer morphology
KW - Performance hysteresis
KW - Platinum-free cathode
KW - Water management
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U2 - 10.1016/j.jpowsour.2020.229407
DO - 10.1016/j.jpowsour.2020.229407
M3 - Article
AN - SCOPUS:85098876985
VL - 487
JO - Journal of Power Sources
JF - Journal of Power Sources
SN - 0378-7753
M1 - 229407
ER -