Electrochemical properties of TiNCrN-coated bipolar plates in polymer electrolyte membrane fuel cell environment

• Published in: Thin solid films Vol. 518; no. 22; pp. 6598 - 6603
• Main Authors: Nam, N.D., Han, J.H., Kim, J.G., Tai, P.H., Yoon, D.H.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2010; Elsevier
• Subjects: Applied sciences; Bipolar plate; Charge transfer; Chromium nitride; Coatings; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Conductivity; Corrosion resistance; Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrical properties of specific thin films; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrochemical impedance spectroscopy; Electrolytes; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Fuel cells; Magnetron sputtering; Materials science; Membranes; Methods of deposition of films and coatings; film growth and epitaxy; Multi-coating; PEMFC; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Titanium nitride; Corrosion resistance; Conductivity; PEMFC; Bipolar plate; Multi-coating; Electrical conductivity; Multilayer; Polymer electrolytes; Chromium nitride; Multiple layer; Titanium nitride; Coatings; X ray diffraction; Layer thickness; Preferred orientation; Electrochemical properties; Physical vapor deposition; Charge transfer; Fuel cell; Stainless steel-316L; Electrochemical impedance spectroscopy
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.03.046

The overall performance of multilayered TiN/CrN coatings suggests that they may show improved corrosion resistance compared to a single layer. Three TiN/CrN coatings deposited on 316L stainless steel substrates by radio frequency magnetron sputtering were evaluated under potentiodynamic, potentiostatic and electrochemical impedance spectroscopy tests. Electrochemical impedance spectroscopy was performed for 168 h in a corrosive environment at 70 °C to determine the coating performance at + 600 mV SCE under the simulated cathodic conditions in a polymer electrolyte membrane fuel cell. The results showed high protective efficiency and charge transfer resistance with decreasing inner layer thickness. X-ray diffraction confirmed the formation of a TiN/CrN(111) preferred orientation along with TiN/CrN (200) at thinner TiN layer.