Research on the performance of carbon film formed on thin stainless steel bipolar plates of PEMFC by laser irradiating

In order to improve the anti-corrosion performance of thin stainless steel bipolar plates of proton exchange membrane fuel cell (PEMFC), the carbon film (of about 0.82-mu m thickness) was fabricated on the thin stainless steel by laser direct writing technology irradiating the formed dense polydopamine (PDA) film. The results indicated that the PDA film has partially transformed into nanocrystalline graphite. Laser power and scanning speed had great effect on the anti-corrosion performance of the final obtained film in simulated PEMFC environment. When the laser power is 3.5 W and the scanning speed is 10 mm/s, the film obtained on the thin stainless steel has the best electrochemical performance in simulated PEMFC environment. Its corrosion current densities were 8.64 mu A.cm(-2)@ -0.1 V (versus SCE) and 1.33 mu A.cm(-2)@ 0.6 V (versus SCE) in simulated anode and cathode environments, respectively. Compared with the bare thin stainless steel, the corresponding corrosion current densities decreased by 45% and 62%. The results obtained in this text provide a novel strategy for modifyingPEMFC thin metal bipolar plates.