Hollow ceramic fibers, precursors for manufacture thereof utilizing nanoparticles, methods of making the same, and methods of using the same

A process for making a composite hollow ceramic fiber, comprising the steps of:

• preparing a core suspension comprising a first polymeric binder, a first particulate ceramic material, and a first solvent;
• preparing a sheath suspension comprising a second polymeric binder, a second particulate ceramic material, and a second solvent;
• providing a spinnerette adapted and configured to continuously extrude one or more nascent hollow fibers comprising a hollow core formed from the core suspension and a sheath surrounding the core formed from the sheath suspension;
• immersing the nascent hollow fiber in a liquid coagulant to facilitate phase inversion of the first and second polymeric binders, wherein:
• the second particulate ceramic material comprises a mixed oxide conductor;
• the second particulate ceramic material has a median particle size less than that of the first particulate ceramic material;
• the first and second particulate ceramic materials are chemically identical;
• the first and second solvents are the same or different;
• and
• the first and second polymeric binders are the same or different.