Plasma-Sprayed (Bi₂O₃)_0.705 (Er₂O₃)_0.245 (WO₃)_0.05 Electrolyte for Intermediate-Temperature Solid Oxide Fuel Cells...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Stabilized bismuth oxide (Bi2O3) with fluorite structure (δ-Bi2O3) is a key electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFCs) due to its high oxygen ion conductivity.
• The ternary system Bi2O3-Er2O3-WO3 is particularly noted for its enhanced ionic conductivity and thermal stability.

Purpose of the Study:

• To investigate the feasibility of depositing dense Bi2O3-Er2O3-WO3 (EWSB) electrolytes using plasma spraying.
• To evaluate the structural and electrical properties of the plasma-sprayed EWSB for IT-SOFC applications.

Main Methods:

• Plasma spraying technique for electrolyte deposition.
• X-ray diffraction (XRD) for phase structure analysis.
• Scanning electron microscopy (SEM) for microstructural characterization.
• Ionic conductivity measurements at elevated temperatures.

Main Results:

• Plasma-sprayed EWSB exhibits a dense microstructure with well-bonded lamellae.
• The material shows high ionic conductivity (0.34 S cm⁻¹ at 750 °C) and excellent stability, with no degradation after prolonged annealing.
• The deposited EWSB electrolyte achieved an ionic conductivity of 0.26 S cm⁻¹ at 750 °C, suitable for direct SOFC application.

Conclusions:

• Plasma spraying is a viable method for producing dense EWSB electrolytes for IT-SOFCs.
• The EWSB material demonstrates promising performance characteristics, including high ionic conductivity and thermal stability.
• The developed EWSB electrolyte can be directly utilized in intermediate-temperature solid oxide fuel cells.