Preparation of a perovskite La0.2Sr0.8CoO3–x membrane on a porous MgO substrate

Crack-free La0.2Sr0.8CoO3–x (LSCO-80) thin films have been fabricated on porous MgO substrates through dip coating followed by sintering. To avoid cracks in the LSCO-80 thin film during sintering caused by the shrinkage mismatch between the film and the substrate, a silver coating on top of the LSCO-80 powder casting layer prior to sintering was found effective. This paper focuses on the control of the porous structure of the MgO substrate, the preparation of sub-micron and narrowly distributed LSCO-80 powder, and the formulation of colloidal suspensions of LSCO-80 powder in an organic medium. The theme of the present work lies in exploiting dip-coating for fabricating a perovskite LSCO-x thin film on asymmetric porous substrates.