Abstract
A novel mechanism based on aliovalent doping, allowing fine tuning of the nanostructure andsurface topography of solution-derived ceria films, is reported. While under reducing atmosphericconditions, non-doped ceria films are inherently polycrystalline due to an interstitial amorphousCe2C3 phase that inhibits grain growth, a high quality epitaxial film can be achieved simply by doping withGd3+ cations. Gd3+ Ce4+ substitutions within the lattice are accompanied by charge-compensating oxygenvacancies throughout the volume of the crystallites acting as an efficientvehicle to reduce the barrier for grain boundary motion caused by interstitialCe2C3. In this way, the original nanostructure is self-purified by pushing the amorphousCe2C3 phase towards the free surface of the film. Once a full epitaxial cube-on-cube oriented ceriafilm is obtained, its surface morphology is dictated by the interplay between faceting on lowenergy {110} and/or {111} pyramidal planes and truncation of those pyramids by (001) ones.The development of the latter requires the suppression of their polar character which isthought to be achieved by charge compensation between the dopand and oxygen along directions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.