Corrosion and conductivity properties of Ni–P/Ti4O7 coating on carbon steel as bipolar plates for proton exchange membrane fuel cells
Anti-Corrosion Methods and Materials
ISSN: 0003-5599
Article publication date: 8 July 2022
Issue publication date: 4 August 2022
Abstract
Purpose
The purpose of this paper is to investigate the interfacial conductivity and corrosion resistance of the Ni–P/Ti4O7 composite coating that is deposited on a carbon steel substrate as bipolar plates for proton exchange membrane fuel cells.
Design/methodology/approach
The Ni–P/Ti4O7 coating was prepared by electroless plating. Scanning electron microscopy, white light interference, energy dispersive spectrometry and X-ray diffraction were used, respectively, to study the surface morphology, chemical composition and phase composition of coated samples. Electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization were used to test the electrochemical performance and corrosion behavior. The interfacial contact resistance (ICR) was measured via the standard method.
Findings
The surface of the Ni–P/Ti4O7 coating is complete and dense and without obvious defects. The electrochemical test results show that the Ni–P/Ti4O7 coating provides better corrosion resistance than the Ni–P coating and substrate. Compared with the Ni–P coating, the ICR of the Ni–P/Ti4O7 coating is lower by about 82.7%. This is because the coating has more conductive contact points. The more exciting thing is that the ICR of the Ni–P/Ti4O7 coating only increases to 12.38 mΩ·cm2 after 5 h of polarization.
Originality/value
This paper provides a method for achieving surface modification of metal bipolar plates. Introducing Ti4O7 particles in the Ni–P layer reduces the contact resistance before and after polarization while ensuring good corrosion resistance.
Keywords
Acknowledgements
This paper was funded by the “The central government guides local science and technology development funds” (2022JH6/100100003).
Citation
Yu, H., Guo, Q., Du, K., Li, D., Wang, C. and Wang, Y. (2022), "Corrosion and conductivity properties of Ni–P/Ti4O7 coating on carbon steel as bipolar plates for proton exchange membrane fuel cells", Anti-Corrosion Methods and Materials, Vol. 69 No. 5, pp. 490-498. https://doi.org/10.1108/ACMM-03-2022-2635
Publisher
:Emerald Publishing Limited
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