A manufacturing method of ceramic powder includes mixing a barium carbonate having a specific surface are of 15 m.sup.2/g or more, a titanium dioxide having a specific surface area of 20 m.sup.2/g or more, a first compound of a donor element having a larger valence than Ti, and a second compound of an acceptor element having a smaller valence than Ti and having a larger ion radium than Ti and the donor element, and synthesizing barium titanate powder by calcining the barium carbonate, the titanium dioxide, the first compound and the second compound until a specific surface area of the barium titanate powder becomes 4 m.sup.2/g or more and 25 m.sup.2/g or less.

The present disclosure relates to a composition that includes a material of at least one of a perovskite structure, a perovskite-like structure, and/or a perovskitoid structure, where the material includes an isotope of an element, the isotope has more neutrons than protons, and the isotope is incorporated into the perovskite structure, the perovskite-like structure, and/or the perovskitoid structure. In some embodiments of the present disclosure, the isotope may make up between greater than 0% and 100% of the element.

A light-emitting layer for a halide perovskite light-emitting device, a method for manufacturing the same and a perovskite light-emitting device using the same are disclosed. The light-emitting layer can be manufactured by forming a first nanoparticle thin film by coating, on a member, a solution comprising halide perovskite nanoparticles having a halide perovskite nanocrystalline structure. Thereby, a nanoparticle light emitter has therein a halide perovskite having a crystal structure in which FCC and BCC are combined; and can show high color purity. In addition, it is possible to improve the luminescence efficiency and luminance of a device by making perovskite as nanoparticles and then introducing the same into a light-emitting layer.

A supported catalyst for decomposing an organic substance that includes a carrier and catalyst particles supported on the carrier. The catalyst particles contain a perovskite-type composite oxide represented by A.sub.xB.sub.yM.sub.zO.sub.w, where A contains at least one of Ba and Sr, B contains Zr, M is at least one of Mn, Co, Ni, and Fe, y+z=1, x>1, z<0.4, and w is a positive value that satisfies electrical neutrality. An organic substance decomposition rate after the supported catalyst is subjected to a heat treatment at 950° C. for 48 hours is greater than 0.97 when the organic substance decomposition rate before the heat treatment is regarded as 1, and an amount of the catalyst particles peeled off when the supported catalyst is ultrasonicated in water at 28 kHz and 220 W for 15 minutes is less than 1 wt % of the catalyst particles before untrasonication.

A dielectric film includes a main component of a complex oxide represented by a general formula of (Sr.sub.1-xCa.sub.x).sub.yTiO.sub.3. 0.40≤x≤0.90 and 0.90≤y≤1.10 are satisfied. A ratio of a diffraction peak intensity on (1, 1, 2) plane of the complex oxide to a diffraction peak intensity on (0, 0, 4) plane of the complex oxide in an X-ray diffraction chart of the dielectric film is 3.00 or more. Instead, a ratio of an intensity of a diffraction peak appearing at a diffraction angle 2θ of 32° or more and 34° or less to an intensity of a diffraction peak appearing at a diffraction angle 2θ of 46° or more and 48° or less in an X-ray diffraction chart of the dielectric film obtained by an X-ray diffraction measurement with Cu-Kα ray as an X-ray source is 3.00 or more.

A dielectric composition includes dielectric particles. At least one of the dielectric particles include a main phase and a secondary phase. The main phase has a main component of barium titanate. The secondary phase exists inside the main phase and has a higher barium content than the main phase.

Perovskite oxides and catalysts containing the perovskite oxides are provided for the thermochemical conversion of carbon dioxide to carbon monoxide. The perovskite oxides can exhibit large carbon monoxide production rates and/or low carbon monoxide production onset temperatures as compared to existing materials. Reactors are provided containing the perovskite oxides and catalysts, as well as methods of use thereof for the thermochemical conversion of carbon dioxide to carbon monoxide.

Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of gadolinium can be added into specific sites in the crystal structure of the synthetic garnet by incorporating indium, a trivalent element. By including both indium and increased amounts of gadolinium, the dielectric constant can be improved. Thus, embodiments of the disclosed material can be advantageous in both above and below resonance applications, such as for isolators and circulators.

An organic matter decomposition catalyst that contains a perovskite type complex oxide represented by A.sub.xB.sub.yM.sub.zO.sub.w, wherein A contains 90 at % or more of at least one element selected from the group consisting of Ba and Sr, B contains 80 at % or more of Zr, M is at least one element selected from the group consisting of Mn, Co, Ni, and Fe, y+z=1, x>1, z<0.4, and w is a positive value that satisfies electrical neutrality.

A light-emitting layer for a halide perovskite light-emitting device, a method for manufacturing the same and a perovskite light-emitting device using the same are disclosed. The light-emitting layer can be manufactured by forming a first nanoparticle thin film by coating, on a member, a solution comprising halide perovskite nanoparticles having a halide perovskite nanocrystalline structure. Thereby, a nanoparticle light emitter has therein a halide perovskite having a crystal structure in which FCC and BCC are combined; and can show high color purity. In addition, it is possible to improve the luminescence efficiency and luminance of a device by making perovskite as nanoparticles and then introducing the same into a light-emitting layer.