TY - JOUR
T1 - Effect of a polybenzimidazole coating on carbon supports for ionomer content optimization in polymer electrolyte membrane fuel cells
AU - Jayawickrama, Samindi Madhubha
AU - Wu, Dan
AU - Nakayama, Rei
AU - Ishikawa, Shota
AU - Liu, Xuanchen
AU - Inoue, Gen
AU - Fujigaya, Tsuyohiko
N1 - Funding Information:
This research was supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan [grant no. 205295 ], under the Nanotechnology Platform Project of MEXT, Japan, KAKENHI [grant no. JP18H01816 ], the Bilateral Program [grant no. AJ190078 ] of the Japan Society for the Promotion of Science, the CREST program [grant no. AJ199002 ] of the Japan Science and Technology Agency, and by the TEPCO Foundation and Fukuoka Financial Group Foundation .
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/6/1
Y1 - 2021/6/1
N2 - Optimizing the ionomer/carbon (I/C) ratio in the catalyst layer (CL) of polymer electrolyte membrane fuel cells (PEMFCs) is vital for maximizing PEMFC efficiency. In this study, the effect of the I/C ratio for a platinum (Pt) catalyst loaded on a polybenzimidazole (PBI)-coated Vulcan (Vulcan/PBI/Pt) is compared with a conventional Pt catalyst on Vulcan (Vulcan/Pt). Furthermore, this study determines that a CL comprising Vulcan/PBI/Pt with an I/C = 0.2 exhibits the highest maximum power density (750 mW cm−2), while that of a CL having Vulcan/Pt is calculated to be 610 mWcm−2 at I/C = 0.6. Effective interactions between ionomer and the PBI-coated Vulcan enables stable ionomer coating and high proton conductivity, even at very low I/C ratios. At such low I/C ratios, the O2 diffusion coefficient of Vulcan/PBI/Pt CL is improved by 51% when compared to Vulcan/Pt CL with an I/C = 0.6. Cross-sectional scanning electron microscopy images further reveal that Vulcan/PBI/Pt CLs possess better pore connectivity than those of Vulcan/Pt. Hence, it concludes that the proposed PBI coating approach is advantageous and significant breakthrough to fabricate highly efficient CLs by improving both proton conduction and O2 diffusion simultaneously with lower ionomer contents.
AB - Optimizing the ionomer/carbon (I/C) ratio in the catalyst layer (CL) of polymer electrolyte membrane fuel cells (PEMFCs) is vital for maximizing PEMFC efficiency. In this study, the effect of the I/C ratio for a platinum (Pt) catalyst loaded on a polybenzimidazole (PBI)-coated Vulcan (Vulcan/PBI/Pt) is compared with a conventional Pt catalyst on Vulcan (Vulcan/Pt). Furthermore, this study determines that a CL comprising Vulcan/PBI/Pt with an I/C = 0.2 exhibits the highest maximum power density (750 mW cm−2), while that of a CL having Vulcan/Pt is calculated to be 610 mWcm−2 at I/C = 0.6. Effective interactions between ionomer and the PBI-coated Vulcan enables stable ionomer coating and high proton conductivity, even at very low I/C ratios. At such low I/C ratios, the O2 diffusion coefficient of Vulcan/PBI/Pt CL is improved by 51% when compared to Vulcan/Pt CL with an I/C = 0.6. Cross-sectional scanning electron microscopy images further reveal that Vulcan/PBI/Pt CLs possess better pore connectivity than those of Vulcan/Pt. Hence, it concludes that the proposed PBI coating approach is advantageous and significant breakthrough to fabricate highly efficient CLs by improving both proton conduction and O2 diffusion simultaneously with lower ionomer contents.
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U2 - 10.1016/j.jpowsour.2021.229855
DO - 10.1016/j.jpowsour.2021.229855
M3 - Article
AN - SCOPUS:85103706225
SN - 0378-7753
VL - 496
JO - Journal of Power Sources
JF - Journal of Power Sources
M1 - 229855
ER -
