Solid oxide cells (SOCs) have important applications as fuel cells and electrolyzers. The application for storage of renewable electricity is also becoming increasingly relevant; however, it is difficult to meet stringent area-specific resistance (ASR) and long-term stability targets needed to achieve required efficiency and cost. Here we show a new SOC that utilizes a very thin Gd-doped ceria (GDC)/yttria-stabilized zirconia (YSZ) bi-layer electrolyte, Ni-YSZ cell support with enhanced porosity, and electrode surface modification using PrOx and GDC nanocatalysts to achieve unprecedented low ASR values < 0.1 Ω cm2, fuel cell power density ∼3 W cm-2, and electrolysis current density ∼4 A cm-2 at 800 °C. Besides this exceptionally high performance, fuel cell and electrolysis life tests suggest very promising stability in fuel cell and steam electrolysis modes. Electrochemical impedance spectroscopy analysis done using a novel impedance subtraction method shows how rate-limiting electrode processes are impacted by the new SOC materials and design.
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)