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Updated: Jun 6, 2025
Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
Promoted Hydride Substitution in BaTiO3 Cubes
Kazunari Arai1, Kaito Onagi2, Ya Tang1
1Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, 4-12-1, Nakanarusawa, Kyoto, Nishikyo-ku 615-8510, Japan.
Abstract:
We report the synthesis of perovskite oxyhydride BaTiO3-H cubes (100-300 nm) using the topochemical hydride reaction of the hydrothermally synthesized oxide. X-ray and neutron diffraction studies revealed that the anion (hydride/oxide) exchange is greatly improved, leading to a maximum hydride content of 0.7, which is higher than previously reported, while no reaction is seen for those with oleic acid on their surface. These results indicate that the well-defined {100} facets, as well as the absence of organic residues, are crucial for promoting hydrogenation. Kissinger analysis on BaTiO2.3H0.7 yielded an activation energy of 165 kJ/mol, much lower than that of BaTiO2.4H0.6 (313 kJ/mol). In contrast to oxides, oxyhydrides with well-defined facets have not been reported before; thus, this study opens new avenues for the rational synthesis of oxyhydride materials with controlled chemical composition and morphology.
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