Composite electrolyte used for low temperature SOFCs to work at 390°C.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Solid oxide fuel cells (SOFCs) are promising energy conversion devices.
• Developing efficient electrolytes for low-temperature SOFCs (LT-SOFCs) is crucial for broader applications.

Purpose of the Study:

• To develop and characterize a novel composite electrolyte for LT-SOFCs.
• To evaluate the performance of SOFCs utilizing the YSZ-BZY composite electrolyte.

Main Methods:

• Fabrication of a symmetrical SOFC using yttria-stabilized zirconia (YSZ) and Ba(NO3)2 powders.
• In situ conversion of the electrolyte into a YSZ-yttrium-doped barium zirconate (BZY) composite at 450°C in a hydrogen atmosphere.
• Characterization using X-ray diffraction and Raman spectroscopy.
• Performance testing of the SOFC at various temperatures.

Main Results:

• The YSZ-Ba(NO3)2 electrolyte successfully converted into a YSZ-BZY composite.
• The YSZ-BZY based fuel cell achieved a maximum power density of 634.06 mW cm-2 at 450°C.
• Stable power density of 300 mW cm-2 was maintained at a reduced temperature of 390°C.
• The composite electrolyte exhibited excellent ion conductivity due to combined proton and oxygen conduction.

Conclusions:

• The developed YSZ-BZY composite electrolyte demonstrates superior performance for LT-SOFCs.
• The enhanced ion conductivity at low temperatures is attributed to synergistic effects between YSZ and BZY.
• This material holds significant potential for advancing LT-SOFC technology.