Fabrication of Indium Tin Oxide Thin Films with Conductivity and Corrosion Resistance for the Metal Separators of Fuel Cells

Abstract

The cost reduction of polymer electrolyte fuel cells (PEFCs) has been demanded to further their industrial application. Separators in a PEFC account for a large portion of their production cost; therefore， the development of low-cost separators with high conductivity and corrosion resistance is key to reducing these costs. Several reports have been published on inexpensive stainless-steel separator coatings with tin dioxide or titanium dioxide. In this research， we focused on the use of indium tin oxide (ITO) to improve safety and to ease implementation, we employed deionized water as a solvent instead of methanol. The resulting ITO thin film showed a contact resistance of 8.8 mΩcm², which is comparable to films made from methanol solvent. ITO thin films also exhibited high corrosion resistance under sulfuric acid solution, similar to the actual PEFC operating environment.