Tokyo Institute of Technology

Japan Science and Technology Agency

Koito Manufacturing Company, Ltd.

Nagoya University

Satoru Matsuishi

Hideo Hosono

Yoshitake Toda

Toshiharu Yokoyama

Michikazu Hara

Masaaki Kitano

Fumitaka Hayashi

Masahiro Hirano

Hisayoshi Daicho

Toshio Kamiya

Yu Shinomiya

Kiminori Enomoto

Yasunori Inoue

Hiroshi Sawa

Sungwng Kim

Akitoshi Nakano

Masashi Miyakawa

Hiroshi Yanagi

Hidenori Hiramatsu

Sung Wng Kim

Yoichi Kamihara

Katsurou Hayashi

Seok Gyu Yoon

Takatoshi Nomura

In a phosphor according to an aspect, an emission site has a perovskite crystal structure expressed by ABX, in which A and B are each a cation and X is an anion, and an emission element is located at a B site serving as a body center of the perovskite crystal structure.

Phosphor

A phosphor is represented by the general formulaMX&#xb7;MMMO:(Re)where Mis at least one atomic element selected from the group consisting of K, Li, Na, Rb, Cs, Fr, Cu, and Ag, with K being essential; Mis at least one atomic element selected from the group consisting of Mg, Ca, Sr, Ba, Ra, Mn, Zn, Cd, and Sn; Mis at least one atomic element selected from the group consisting of P, V, Nb, Ta, As, Sb, and Bi; X is at least one halogen element, with F being essential; Re is at least one atomic element selected from the group consisting of rare earth elements, with Eu being essential; and a is in the range 0.6&#x2264;a&#x2264;1.4.

If a conductive mayenite compound having a large specific surface area is obtained, the usefulness thereof in respective applications is remarkably increased. A conductive mayenite compound powder having a conduction electron density of 10cmor more and a specific surface area of 5 mgor more is produced by: the following steps: (1) forming a precursor powder by subjecting a mixture of a starting material powder and water to a hydrothermal treatment; (2) forming a mayenite compound powder by heating and dehydrating the precursor powder; (3) forming an activated mayenite compound powder by heating the compound powder in an inert gas atmosphere or in a vacuum; and (4) injecting electrons into the mayenite compound through a reduction treatment by mixing the activated mayenite compound powder with a reducing agent.

Method for producing conductive mayenite compound powder having large specific surface area

If a conductive mayenite compound having a large specific surface area is obtained, the usefulness thereof in respective applications is remarkably increased. A conductive mayenite compound powder having a conduction electron density of 10cmor more and a specific surface area of 5 mgor more is produced by: (1) a step for forming a precursor powder by subjecting a mixture of a starting material powder and water to a hydrothermal treatment; (2) a step for forming a mayenite compound powder by heating and dehydrating the precursor powder; (3) a step for forming an activated mayenite compound powder by heating the compound powder in an inert gas atmosphere or in a vacuum; and (4) a step for injecting electrons into the mayenite compound through a reduction treatment by mixing the activated mayenite compound powder with a reducing agent.

Method for producing conductive mayenite compound powder

The present invention provides a catalyst substance that is stable and performs well in the synthesis of ammonia, one of the most important chemical substances for fertilizer ingredients and the like. The catalyst substance exhibits catalytic activity under mild synthesis conditions not requiring high pressure, and is also advantageous from a resource perspective. Further provided is a method for producing the same. This catalyst comprises a supported metal catalyst that is supported on a mayenite type compound including conduction electrons of 10cmor more and serving as a support for the ammonia synthesis catalyst. The mayenite type compound used as the support may take any form, including that of powder, a porous material, a sintered body, a thin-film, or a single crystal. Use of this catalyst makes it possible to increase the electron donating ability toward a transition metal.

Ammonia synthesis catalyst and ammonia synthesis method

Provides a new non-oxide system compound material superconductor as an alternative of the perovskite type copper oxides superconductor. Layered compounds which are represented by chemical formula AF(TM)Pn (wherein, A is at least one selected from a group consisting of the second family elements in the long form periodic table, F is a fluorine ion, TM is at least one selected from a group of transition metal elements consisting of Fe, Ru, Os, Ni, Pd, and Pt, and Pn is at least one selected from a group consisting of the fifteenth family elements in the long form periodic table), having a crystal structure of ZrCuSiAs type (space group P4/nmm) and which become superconductors by doping trivalent cations or divalent anions.

Layered compound, superconductor and method for producing same

In an electride C12A7 provided by replacing free oxygen in 12CaO.7AlOwith electrons, a material having metallic electroconductivity and an electric conductivity of more than 5&#xd7;10S/cm at room temperature could not have been produced without difficulties. An electride 12CaO.7AlO, which has metallic electroconductivity and has an electric conductivity of more than 5&#xd7;10S/cm at room temperature, can be produced by heat-treating titanium metal vapor and 12CaO.7AlOsingle crystal, sinter, or thin film at a temperature above 600&#xb0; C. and below 1,450&#xb0; C. for less than 240 hours. Further, thermoelectric field electron release can also be realized using an electron release chip fabricated from the electride.

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Growing community of inventors

Tokyo, Japan

Satoru Matsuishi