Optimizing the interfacial potential distribution to mitigate high transient potential induced dissolution on C/Ti coated metal bipolar plates used in PEMFCs

• Published in: Corrosion science Vol. 208; p. 110686
• Main Authors: Wang, Xian-Zong, Zhang, Meng-Meng, Hu, Qian, Su, Shuo, Fan, Hong-Qiang, Wang, Haifeng, Luo, Jing-Li
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2022
• Subjects: C/Ti coating; Cathodic transient potentials; Corrosion resistance; Interfacial contact resistance; Metal bipolar plates; Proton exchange membrane fuel cells; Corrosion resistance; Cathodic transient potentials; Interfacial contact resistance; Proton exchange membrane fuel cells; C/Ti coating; Metal bipolar plates
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2022.110686

Developing a conductive and corrosion-resistant coating on metal bipolar plates is essential to mitigate the degradation induced by the high cathodic transient potentials of proton exchange membrane fuel cells. In this work, a multilayer nanoscale C/Ti coating is prepared on SS316L (C/Ti/SS). The C/Ti/SS achieves a highly prominent ICR of 1.59 mΩ cm2 and corrosion rate of 2 × 10–8 A/cm2, remarkably better than the targets. Analysis of coating microstructure and composition suggests that the significantly enhanced corrosion resistance is attributed to the diffusional interfaces which optimize the potential distribution across the coating and improve the transpassive potential of C/Ti/SS. [Display omitted] •Multilayered C/Ti coating with diffusional interfaces is prepared on SS316L (C/Ti/SS).•Coating interfaces optimize the across-sectional potential distribution.•C/Ti/SS achieves high corrosion resistance and conductivity simultaneously.•C/Ti/SS possesses a remarkably high transpassive potential of 1.5 V vs. SHE.•C/Ti/SS mitigates the dissolution induced by the high cathodic transient potential.