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Atomic Layer Deposition of GdCoO₃ and Gd_0.9Ca_0.1CoO₃.

ABSTRACT: Thin films of the catalytically interesting ternary and quaternary perovskites GdCoO₃ and Gd_0.9Ca_0.1CoO₃ are fabricated by atomic layer deposition using metal ?-diketonates and ozone as precursors. The resulting thin films are amorphous as deposited and become single-oriented crystalline on LaAlO₃(100) and YAlO₃(100/010) after post-annealing at 650 °C in air. The crystal orientations of the films are tunable by choice and the orientation of the substrate, mitigated through the interface via solid face epitaxy upon annealing. The films exhibit no sign of Co²⁺. Additionally, high-aspect-ratio Si(100) substrates were used to document the suitability of the developed process for the preparation of coatings on more complex, high-surface-area structures. We believe that coatings of GdCoO₃ and Gd_1-xCa_xCoO₃ may find applications within oxidation catalysis.

SUBMITTER: Duparc M

PROVIDER: S-EPMC6982051 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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