High-Performance Metal-Supported Protonic Ceramic Fuel Cell Utilizing Ammonia-Derived Fuel

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Metal-supported protonic ceramic fuel cells (MS-PCFCs) show promise for ammonia-based energy conversion.
• Development is hindered by challenges in cosintering, fuel electrode reduction, and chemical stability in ammonia (NH₃).

Purpose of the Study:

• To investigate and overcome the coupled challenges in Ni-metal-supported PCFCs for ammonia utilization.
• To establish a fabrication window for cosintering dense electrolytes with porous Ni supports.
• To optimize performance and long-term stability of MS-PCFCs under ammonia.

Main Methods:

• Correlated reduction conditions and electrolyte processing to identify a fabrication window for BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3-δ (BZCYYb1711) electrolyte and Ni support.
• Incorporated an anode functional layer to improve interfacial compatibility and reduce ohmic resistance.
• Employed an upstream NH₃ predecomposition strategy for long-term ammonia operation testing.

Main Results:

• Identified a fabrication window enabling cosintering of dense BZCYYb1711 electrolyte with porous Ni support, maintaining structural integrity.
• Achieved peak power densities of 0.72 W cm^-2 with NH₃ and 1.05 W cm^-2 with H₂ at 700 °C.
• Demonstrated stable operation for 300 hours under NH₃ at 600 °C.

Conclusions:

• Established practical processing and microstructural insights for Ni-based MS-PCFCs operated with ammonia.
• The developed fabrication strategy and operational approach enable stable and efficient ammonia utilization in MS-PCFCs.