High-temperature catalyst supports and ceramic membranes: Metastability and particle packing

Parameters and/or processes responsible for the stability of catalyst supports and ceramic membranes are discussed. Two major parameters/processes were identified which are responsible for the stability of sol‐gel derived nanostructured oxides at elevated temperatures. They are metastable‐to‐stable phase transformation and structure and packing of primary particles within the aggregate. Based on these observations, strategies to develop thermostable nanostructured oxides for high‐temperature membrane and catalyst applications are discussed by taking titania and titania‐alumina nanocomposites as examples.