Japan Science and Technology Agency

Asahi Glass Company, Limited

Sungwng Kim

Hideo Hosono

Masahiro Hirano

Masashi Miyakawa

Toshio Kamiya

Satoru Matsuishi

Setsuro Ito

Yoshitake Toda

Katsuro Hayashi

Hiroshi Yanagi

Hidenori Hiramatsu

Satoru Narushima

Yoichi Kamihara

Katsurou Hayashi

Seok Gyu Yoon

Takatoshi Nomura

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.

[object Object]

To provide a method for preparing a mayenite type compound having electroconductivity imparted. A method for preparing an electroconductive mayenite type compound, which comprises melting a raw material containing Al and at least one element selected from the group consisting of Ca and Sr, holding the melt in a low oxygen partial pressure atmosphere having an oxygen partial pressure of not higher than 10 Pa, followed by cooling or annealing in a low oxygen partial pressure atmosphere or in atmospheric air for solidification, thereby to replace oxygen present in cages by electrons in a high concentration.

Method for preparing electroconductive mayenite type compound

Growing community of inventors

Kanagawa, Japan

Sungwng Kim