Modification and durability of carbon paper gas diffusion layer in proton exchange membrane fuel cell.

To solve the durability problem caused by carbon corrosion in the porous carbon paper gas diffusion layer (GDL) of proton exchange membrane fuel cell (PEMFC), a Cr 7 C 3 ceramic coating on porous carbon paper by molten salt method was prepared. The obtained Cr 7 C 3 coating is dense and shows good adherent with the carbon paper. Based on the corrosion resistance testes, it is concluded that the Cr 7 C 3 coated carbon paper can keep high chemical stability in the long-time acid immersion accelerated corrosion tests and simulated cathodic proton exchange membrane fuel cells environment. The carbon paper with Cr 7 C 3 coating shows a small current density with a value of about 1.1 × 10−5 A cm−2 in the potentiostatic polarization test under 1 M H 2 SO 4 + 2 ppm HF at 70 °C and1.4 V SCE for 72 h. Meanwhile, the resistivity of carbon paper with Cr 7 C 3 coating prepared is 30% lower than that of pure carbon paper, and the conductivity is 1.5 times that of pure carbon paper. [ABSTRACT FROM AUTHOR]