Energetic Deposition of Fully Dense, High-Quality Doped-Ceria Coatings for Solid Oxide Fuel Cells

Fuel cells convert chemical energy in a fuel directly to electrical power. They have several advantages over other energy sources including: highly efficient energy conversion, fuel flexibility, reduced air pollution, reduced greenhouse gas emissions, reduced oil consumption, and expanded use of renewable power. State-of-the-art Solid Oxide Fuel Cells (SOFC) use lanthanum strontium cobalt iron oxide (LSCF) cathodes with a yttria stabilized zirconia (YSZ) electrolyte. During operation the LSCF tends to react with the YAZ forming Sr-zirconate, which is an electrical insulator, resulting in poor performance. Studies have shown that a Pulse Laser Deposition (PLD) coating of Sm-doped Ceria (SDC) or Gd-doped Ceria (GDC) between the LSCF and YAZ can act as an effective diffusion barrier enhancing the performance of the SOFC and extending its life. The problem is PLD is not a scalable process and is not economically viable so manufacturing of advanced SOFCs using this process is not feasible. A process needs to be found that will allow highly efficient, state-of-the-art SOFCs to be manufactured and commercialized. The purpose of this project is to demonstrate an Energetic Deposition Process (EDP) that can be used to deposit high-quality SDC layers on a very large industrial scale at low cost, thereby allowing state-of-the- art SOFCs to be manufactured and commercialized. The EDP process produces dense, well adhering films because of the high-energy ions that are naturally produced during deposition. The dense coatings produced by EDP are virtually identical to those produced by PLD, which has already been demonstrated to provide an excellent SDC diffusion barrier coating for SOFCs. EDP is an industrial process that can be used for large-scale manufacturing at low cost. The benefits of this project are that is will allow state-of-the-art, highly efficient solid oxide fuel cells to be manufactured on a large, industrial scale at low cost. This will lead to a significant reduction in the cost and allow LSCF SOFCs to be commercialized. This will help the United States become energy independent, reduce the consumption of fossil fuels, and will reduce the production of greenhouse gasses and air pollution.