Anion-Doped Perovskite Oxygen-Permeable Membranes Fabricated via an Improved One-Step Thermal Processing Approach

Area of Science:

• Materials Science
• Chemical Engineering
• Membrane Technology

Background:

• Anion-doped perovskite hollow fiber membranes show promise for oxygen separation.
• Fabrication challenges include elemental and anion dissolution when using deionized water.

Purpose of the Study:

• To develop an improved fabrication method for anion-doped perovskite hollow fiber membranes.
• To prevent elemental dissolution during the fabrication process.
• To enhance oxygen separation performance and membrane stability.

Main Methods:

• A one-step thermal processing approach using saturated solutions as internal and external coagulation baths.
• Utilizing a fluorine-containing saturated solution as a coagulation bath.
• Controlling the stoichiometric ratio during fabrication.

Main Results:

• The improved method effectively prevented metal and anion element dissolution.
• Using a fluorine-containing saturated solution increased membrane oxygen flux by 21% at 900 °C compared to deionized water.
• Achieved oxygen permeability of 6 mL cm⁻² min⁻¹ at 900 °C and oxygen flux > 1 mL cm⁻² min⁻¹ at 700 °C, meeting commercial standards.

Conclusions:

• The one-step thermal processing with saturated solutions is an effective strategy for fabricating high-performance anion-doped perovskite hollow fiber membranes.
• Fluorine doping and optimized fabrication enhance oxygen flux and stability.
• Further advancements in anion doping and stability strategies will drive practical applications.