title: Quantitative visualization of a gas diffusion layer in a polymer electrolyte fuel cell using synchrotron X-ray imaging techniques.
abstract: A gas diffusion layer (GDL) in a polymer electrolyte fuel cell (PEFC) is quantitatively visualized using synchrotron X-ray micro-computed tomography. For three-dimensional reconstruction, an adaptive threshold method is used. This method is compared with the conventional method, i.e. Otsu's method. Additionally, the spatial and temporal variations of the porosity distribution of the GDL under freeze-and-thaw cycles are investigated experimentally. The freeze-and-thaw cycles are established simply using a CRYO system and light source illumination, respectively. Structural defects are found to largely affect the porosity of the GDL. In addition, a cyclic porosity variation is observed in the GDL under freeze-and-thaw cycles. The heterogeneous porosity is irreversibly decreased with the progress of repetitive cycles.
authors: Center for Biofluid and Biomimic Research, Department of Mechanical Engineering, Pohang University of Science and Technology, San 31, Hyoja Dong, Namgu, Pohang, Republic of Korea.
authors: Seung Gon
authors: SG
authors: Kim
authors: Sang Joon
authors: SJ
authors: Lee
keywords: X-ray tomography; freeze-and-thaw cycle; gas diffusion layer; polymer electrolyte fuel cell; porosity distribution