Corrosion behavior of Ti–Pt-coated stainless steel for bipolar plates in polymer electrolyte membranes under water electrolysis conditions
Sin-Jae Kang,
Geon-Il Kim,
Seung-Hyun Kim,
Ji-Han Lee,
Jeong-Soo Kim,
Seong-Un Im,
Yeon-Soo Kim,
Jung-Gu Kim
Affiliations
Sin-Jae Kang
School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Gu, Suwon-si, Gyeonggi-do, 16419, South Korea
Geon-Il Kim
School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Gu, Suwon-si, Gyeonggi-do, 16419, South Korea
Seung-Hyun Kim
School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Gu, Suwon-si, Gyeonggi-do, 16419, South Korea
Ji-Han Lee
Water Electrolyzer Engineering Design Team, R&D Division, Hyundai Motor Company,17-5, Mabuk-ro 240 beongil, Giheung-gu, Yongin-si, Gyeonggi-do, 16891, South Korea
Jeong-Soo Kim
Water Electrolyzer Engineering Design Team, R&D Division, Hyundai Motor Company,17-5, Mabuk-ro 240 beongil, Giheung-gu, Yongin-si, Gyeonggi-do, 16891, South Korea
Seong-Un Im
Water Electrolyzer Engineering Design Team, R&D Division, Hyundai Motor Company,17-5, Mabuk-ro 240 beongil, Giheung-gu, Yongin-si, Gyeonggi-do, 16891, South Korea
Yeon-Soo Kim
Water Electrolyzer Engineering Design Team, R&D Division, Hyundai Motor Company,17-5, Mabuk-ro 240 beongil, Giheung-gu, Yongin-si, Gyeonggi-do, 16891, South Korea
Jung-Gu Kim
School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Gu, Suwon-si, Gyeonggi-do, 16419, South Korea; Corresponding author.
In this study, the corrosion behavior and degradation mechanism of Ti–Pt-coated stainless steel bipolar plates were investigated through electrochemical tests and surface analysis in a polymer electrolyte membrane water electrolysis (PEMWE) operating environment. The coated bipolar plate has a corrosion current density of only 1.68 × 10−8 A/cm2, which is an order of magnitude lower than that of the bare SS316L substrate (1.94 × 10−7 A/cm2), indicating that its corrosion resistance is superior to that of bare SS316L substrate. However, in the PEMWE operating environment, the protection efficiency of the coating and the corrosion resistance of the coated bipolar plate decreased. The degradation of the coated bipolar plate can be attributed to electrolyte penetration into the blistering areas of the coating layer with micro voids. Defects in the coating layer occur because of the pressure of oxygen gas generated within the coating layer under high-potential conditions, thereby exposing the substrate to the electrolyte and corrosion.
