1. Titanium oxynitride films for a bipolar plate of polymer electrolyte membrane fuel cell prepared by inductively coupled plasma assisted reactive sputtering
- Author
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Donguk Han, Junhoe Kim, Suzi Kim, and J.J. Lee
- Subjects
Materials science ,Renewable Energy, Sustainability and the Environment ,Contact resistance ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Proton exchange membrane fuel cell ,Oxygen ,Titanium nitride ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Sputtering ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,Inductively coupled plasma ,Tin ,Titanium - Abstract
Titanium oxynitride (TiN x O y ) films are investigated for application as a bipolar plate coating material in a polymer electrolyte membrane fuel cell (PEMFC). TiN x O y films with various amounts of oxygen are deposited on stainless-steel substrates by inductively coupled plasma (ICP) assisted reactive sputtering by changing the oxygen gas flow rate. The interfacial contact resistance (ICR) and the corrosion resistance of the TiN x O y films are measured under PEMFC simulated conditions. When the amount of oxygen in the TiN x O y film is approximately 2 flow rate ≤0.2 sccm), the corrosion resistance is enhanced considerably, whereas the interfacial contact resistance does not change. The corrosion current density decreases from 8 × 10 −6 A cm −2 for the TiN-coated sample to 2.7 × 10 −6 A cm −2 at 0.6 V vs. SCE as a result of oxygen incorporation in the TiN film. The ICR value remains at 2.5 mΩ cm 2 at 150 N cm −2 . When a small amount of oxygen is added to the TiN film, it is postulated that the oxygen atoms locate at the column and grain boundaries, and thus prevent corrosive media from penetrating into the substrate while not deteriorating the electrical property of the film.
- Published
- 2009
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