SnO2:F Coated Ferritic Stainless Steels for PEM Fuel Cell Bipolar Plates

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2007.04.028· OSTI ID:915673

Wang, H; Turner, J A

Ferrite stainless steels (AISI441, AISI444, and AISI446) were successfully coated with 0.6 {micro}m thick SnO{sub 2}:F by low-pressure chemical vapor deposition and investigated in simulated PEMFC environments. The results showed that a SnO{sub 2}:F coating enhanced the corrosion resistance of the alloys in PEMFC environments, though the substrate steel has a significant influence on the behavior of the coating. ICP results from the testing solutions indicated that fresh AISI441 had the highest dissolution rates in both environments, and coating with SnO2:F significantly reduced the dissolution. Coating AISI444 also improved the corrosion resistance. Coating AISI446 steel further improved the already excellent corrosion resistance of this alloy. For coated steels, both potentiostatic polarizations and ICP results showed that the PEMFC cathode environment is much more corrosive than the anode one. More dissolved metallic ions were detected in solutions for PEMFC cathode environment than those in PEMFC anode environment. Sn{sup 2+} was detected for the coated AISI441 and AISI444 steels but not for coated AISI446, indicating that the corrosion resistance of the substrate has a significant influence on the dissolution of the coating. After coating, the ICR values of the coated steels increased compared to those of the fresh steels. The SnO{sub 2}:F coating seems add an additional resistance to the native air-formed film on these stainless steels.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO.
• Sponsoring Organization: USDOE
• DOE Contract Number: AC36-99GO10337
• OSTI ID: 915673
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Journal Issue: 2, 2007 Vol. 170; ISSN JPSODZ; ISSN 0378-7753
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
36 MATERIALS SCIENCE
ALLOYS
ANODES
CATHODES
CHEMICAL VAPOR DEPOSITION
COATINGS
CORROSION RESISTANCE
DISSOLUTION
FERRITE
FUEL CELLS
Hydrogen
PLATES
STAINLESS STEELS
STEELS
SUBSTRATES
TESTING