YSZ freestanding films from hybrid polymer–oxide composites by the sol–gel process: Influence of polymer features on ceramic microstructure

Hybrid polymer–yttria–zirconia xerogels have been used to prepare freestanding and crack free cubic yttria-stabilized zirconia (YSZ) films. Depending on the final ceramic properties, these materials could find application as components in solid oxide fuel cells. Different types of organic and bioorganic molecules such as albumin, starch, sucrose, dextran, carboxymethylcellulose, and polyvinyl alcohol, have been studied in order to prepare polymer–oxide nanocomposites. The reason for adding a polymer to a sol–gel-derived inorganic network stays in avoiding cracks formation during the pyrolysis process, which converts the preceramic into the ceramic material. Polymers behave as stress relaxing agents and allow obtaining dense and crack free final ceramics. fferences in polymer chemical structure and solubility impose variable synthesis procedures, and limit the availability of suitable yttria precursors. We present here a study concerning the influence of different polymers on the microstructural properties of yttria–zirconia films. Thermogravimetric analyses (TGA), SEM, XRD, N2 sorption and density measurements have been used to characterize the polymer-to-ceramic transformation and the final ceramic materials.