Selective Epitaxial Growth of CaNH and CaNH Thin Films by Reactive Magnetron Sputtering under Hydrogen Partial Pressure Control.

Calcium compounds with N and H are promising catalysts for NH conversion, and their epitaxial thin films provide a platform to quantitatively understand the catalytic activities. Here we report the selective epitaxial growth of CaNH and CaNH thin films by controlling the hydrogen partial pressure () during reactive magnetron sputtering. We find that the hydrogen charge states can be tuned by : CaNH containing H is formed at < 0.

Heteroepitaxial Growth of a TaN Thin Film with Clear Anisotropic Optical Properties.

TaN is a promising semiconductor photocatalyst which can generate H gas from water under visible light illumination. It is expected that TaN exhibits a strong anisotropy in its physical properties stemming from its highly anisotropic crystal structure. However, such anisotropic properties have not been verified experimentally due to the difficulty in synthesizing a large single crystal.

Strain-induced creation and switching of anion vacancy layers in perovskite oxynitrides.

Perovskite oxides can host various anion-vacancy orders, which greatly change their properties, but the order pattern is still difficult to manipulate. Separately, lattice strain between thin film oxides and a substrate induces improved functions and novel states of matter, while little attention has been paid to changes in chemical composition. Here we combine these two aspects to achieve strain-induced creation and switching of anion-vacancy patterns in perovskite films.

High-Quality Heteroepitaxial Growth of Thin Films of the Perovskite Oxynitride CaTaON: Importance of Interfacial Symmetry Matching between Films and Substrates.

Perovskite oxynitrides have been studied with regard to their visible light-driven photocatalytic activity and novel electronic functionalities. The assessment of the intrinsic physical and/or electrochemical properties of oxynitrides requires the epitaxial growth of single-crystalline films. However, the heteroepitaxy of perovskite oxynitrides has not yet matured compared to the progress realized in work with perovskite oxides.