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Guided cracking of electrodes by stretching prism-patterned membrane electrode assemblies for high-performance fuel cells.

ABSTRACT: Guided cracks were successfully generated in an electrode using the concentrated surface stress of a prism-patterned Nafion membrane. An electrode with guided cracks was formed by stretching the catalyst-coated Nafion membrane. The morphological features of the stretched membrane electrode assembly (MEA) were investigated with respect to variation in the prism pattern dimension (prism pitches of 20 ?m and 50 ?m) and applied strain (S???0.5 and 1.0). The behaviour of water on the surface of the cracked electrode was examined using environmental scanning electron microscopy. Guided cracks in the electrode layer were shown to be efficient water reservoirs and liquid water passages. The MEAs with and without guided cracks were incorporated into fuel cells, and electrochemical measurements were conducted. As expected, all MEAs with guided cracks exhibited better performance than conventional MEAs, mainly because of the improved water transport.

SUBMITTER: Ahn CY

PROVIDER: S-EPMC5775251 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Guided cracking of electrodes by stretching prism-patterned membrane electrode assemblies for high-performance fuel cells.

Ahn Chi-Yeong CY Jang Segeun S Cho Yong-Hun YH Choi Jiwoo J Kim Sungjun S Kim Sang Moon SM Sung Yung-Eun YE Choi Mansoo M

Scientific reports 20180119 1

Guided cracks were successfully generated in an electrode using the concentrated surface stress of a prism-patterned Nafion membrane. An electrode with guided cracks was formed by stretching the catalyst-coated Nafion membrane. The morphological features of the stretched membrane electrode assembly (MEA) were investigated with respect to variation in the prism pattern dimension (prism pitches of 20 μm and 50 μm) and applied strain (S ≈ 0.5 and 1.0). The behaviour of water on the surface of the c ...[more]

PMID: 29352249

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Dataset Information

Guided cracking of electrodes by stretching prism-patterned membrane electrode assemblies for high-performance fuel cells.

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Guided cracking of electrodes by stretching prism-patterned membrane electrode assemblies for high-performance fuel cells.

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