TY: THES T1 - Hydrothermally-activated ceramic membranes for oxygen separation A1 - Vieira, Miguel Amado N2 - The present work focuses on new strategies of the surface activation of ceramic membranes for oxygen separation involving hydrothermal processing. Such an approach is particularly relevant for membranes with complex shapes, for which the deposition of the surface activating agent by conventional methods might be complicated or even impossible. A model membrane material, (SrFe)???(SrAl?)???O?, consisting of two phases, the strontium-deficient perovskite Sr(Fe,Al)O??? responsible for the ionic transport properties and the monoclinic SrAl?O? phase responsible for adequate thermomechanical properties, was considered. The hydrothermal treatment was based on several top-down type and bottom-up type approaches, leading to controlled modification of the membrane surface. Following oxygen permeation studies under relevant operating conditions have shown that a significant enhancement of the oxygen flux through modified membranes can be achieved, providing a convincing proof-of-concept of the proposed strategies. UR - https://ria.ua.pt/handle/10773/34242 Y1 - 2022 PB - No publisher defined