Degradation of gas diffusion layers through repetitive freezing

Yongtaek Lee, Bosung Kim, Yong Chan Kim, Xianguo Li

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

This work investigates the degradation of an individual gas diffusion layer (GDL) by repeated freezing cycles. The pore size distribution, gas permeability, surface structure, and contact angle on the surface of the GDL were measured in four different types of GDL: SGL paper with a microporous layer (MPL); SGL paper with 5. wt% of polytetrafluoroethylene (PTFE) loading; Toray paper without PTFE loading; and Toray paper with 20. wt% of PTFE loading. After repeated freezing cycles, the porosity of the GDL without PTFE was reduced by 27.2% due to the volumetric expansion of the GDL. The peak of the log differential intrusion moved toward a smaller pore diameter slightly because of the repeated freezing process. The crack of the MPL increased in its width and length after repeated freezing cycles. The through-plane gas permeability of the GDL with the MPL doubled after repeated freezing cycles due to the growth of the crack in the MPL, but was very small for the GDLs with Toray paper. Besides, the GDLs with PTFE loading showed a relatively larger decrease in the contact angle on the surface than the GDL without PTFE loading due to the separation of PTFE from the carbon fiber during the repeated freezing process.

Original languageEnglish
Pages (from-to)5111-5119
Number of pages9
JournalApplied Energy
Volume88
Issue number12
DOIs
Publication statusPublished - 2011 Dec 1

Fingerprint

Diffusion in gases
Polytetrafluoroethylenes
Freezing
Degradation
Gas permeability
Contact angle
Cracks
Surface structure
Carbon fibers
Pore size
Porosity

Keywords

  • Contact angle
  • Freezing
  • Gas diffusion layer
  • Microporous layer
  • Permeability
  • Porosimetry

ASJC Scopus subject areas

  • Energy(all)
  • Civil and Structural Engineering
  • Mechanical Engineering
  • Nuclear Energy and Engineering
  • Fuel Technology
  • Energy Engineering and Power Technology

Cite this

Degradation of gas diffusion layers through repetitive freezing. / Lee, Yongtaek; Kim, Bosung; Kim, Yong Chan; Li, Xianguo.

In: Applied Energy, Vol. 88, No. 12, 01.12.2011, p. 5111-5119.

Research output: Contribution to journalArticle

Lee, Yongtaek ; Kim, Bosung ; Kim, Yong Chan ; Li, Xianguo. / Degradation of gas diffusion layers through repetitive freezing. In: Applied Energy. 2011 ; Vol. 88, No. 12. pp. 5111-5119.
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