CF4 plasma treatment for preparing gas diffusion layers in membrane electrode assemblies

A technical review on gas diffusion, mechanism and medium of PEM fuel cell

“…A study by Park et al [63] indicated that the optimized PTFE content of GDM resulted in an effective water management and improved oxygen gas diffusion kinetics in the membrane-electrode assembly. Pai et al [64] observed that the usage of carbon tetra fluoride plasma will effectively improve the hydrophobic property of GDM and the plasma treatment can modify the surface morphologies of the wet-proofed GDL to enhance the fuel cell performance without the usage of expensive electro catalytic elements. The method of coating the GDL with an entirely new chemical, namely fluoro alkyl silane (FAS) having strong hydrophobic ligands as well as siloxane bonds was introduced by Yoon et al [65] and they inferred that FAS-treated carbon paper has an extremely thin and uniform coating surface compared to PTFE, showing that they are firmly formed on carbon fibres without any flaking-off.…”

“…Kannan et al [89] have also studied the usage of single-walled CNT as an effective MPL for fabricating GDL. The GDL fabricated by the use of pure black carbon (jointly developed by a superior graphite company and Columbian Chemicals Company) exhibits superior performance in hydrogen/air system without any back pressure [64]. The PEM fuel cell performance has been compared using non-processed Ketjenblack EC-600JD and Vulcan XC-72 as the MPL material [90,91], and better performances were observed with high-surface-area Ketjen black.…”

Development of carbon nanotubes based gas diffusion layers by in situ chemical vapor deposition process for proton exchange membrane fuel cells

“…Several GDL fabrication techniques have been investigated in the past, which include low-shear coating, rod coating, screen-printing, doctor blade, impregnation, etc. [6][7][8][9][10][11]. It is worth mentioning that the dry fabrication involves dry deposition of a mixture of carbon black and polytetrafluoroethylene powders onto water-proofed carbon paper in combination with a subsequent rolling process [12].…”

Nano-Roughened Teflon-Like Film Coated Polyethylene Terephthalate Substrate with Trifluoromethane Plasma Enhanced Hydrophobicity and Transparency

“…Raising the fluorine atom concentration in fluorocarbon plasma up to a saturated condition, the ion bombardment is initiated with F/C precursor ratio of 4 or larger to suppress polymerization by the enhanced etching process. 13,14 With the growth of Teflon-like film at F/C precursor ratio of 3, the water-repellent nano-roughened surface reveals a large water contact angle h c > 108 ( Fig. 1 inset) as compared to that of the bare PET substrate with h c of only 78 .…”