Publications by authors named "Masatoshi Ohkura"
Article Synopsis
- Oxynitrides have unique properties, including visible-light absorption and photocatalytic activity, sparking interest in their synthesis, which usually requires high temperatures (800-1,300 °C) and presents challenges due to reducing conditions.
- A new method allows for oxynitride preparation at lower temperatures (<500 °C) using a perovskite oxyhydride as a host, enabling an exchange between hydride and nitride ions.
- This process leads to the creation of a room-temperature ferroelectric material and hints at broader applications for exploring other mixed anionic compounds.
The oxyhydride solid solutions (Ca,Sr)TiO(3-x)H(x) and (Sr,Ba)TiO(3-x)H(x) have been prepared by reducing the corresponding ATiO(3) oxides with calcium hydride. Under the reaction conditions examined, a hydride content of x = 0.1-0.
View Article and Find Full Text PDFIn oxides, the substitution of non-oxide anions (F(-),S(2-),N(3-) and so on) for oxide introduces many properties, but the least commonly encountered substitution is where the hydride anion (H(-)) replaces oxygen to form an oxyhydride. Only a handful of oxyhydrides have been reported, mainly with electropositive main group elements or as layered cobalt oxides with unusually low oxidation states. Here, we present an oxyhydride of the perhaps most well-known perovskite, BaTiO(3), as an O(2-)/H(-) solid solution with hydride concentrations up to 20% of the anion sites.
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