Thermoelectric conversion material and its manufacturing method, and thermoelectric conversion device using the same

Abstract

Disclosed is a new thermoelectric conversion material represented by the chemical formula 1: Bi 1-x Cu 1-y O 1-z Te, where 0≦x<1, 0≦y<1, 0≦z<1 and x+y+z>0. A thermoelectric conversion device using said thermoelectric conversion material has good energy conversion efficiency.

What is claimed is: 
     
         1 . Thermoelectric conversion materials BiCuOTe having a natural super-lattice structure in which BiTeCu layers alternate with O layers along a c-crystalline axis, wherein at least one element selected from the group consisting of Bi, Cu and O is partially deficient. 
     
     
         2 . The thermoelectric conversion materials according to  claim 1 ,
 wherein, when each of x, y and z is a ratio of the deficiency in Bi, Cu and O, respectively, the x, y and z satisfy the following relations:   0≦x≦0.5, 0≦y≦0.5 and 0≦z≦0.5.   
     
     
         3 . The thermoelectric conversion materials according to  claim 2 ,
 wherein the x, y and z satisfy the following relations:   0≦x≦0.2, 0≦y≦0.2 and 0≦z≦0.2.   
     
     
         4 . The thermoelectric conversion materials according to  claim 3 ,
 wherein the x, y and z satisfy the following relations:   0≦x≦0.1, y=0 and z=0.   
     
     
         5 . The thermoelectric conversion materials according to  claim 3 ,
 wherein the x, y and z satisfy the following relations:   x=0, 0<y≦0.2 and z=0.   
     
     
         6 . The thermoelectric conversion materials according to  claim 3 ,
 wherein the x, y and z satisfy the following relations:   0<x≦0.1, y=0 and 0<z≦0.1.   
     
     
         7 . A method for manufacturing thermoelectric conversion materials defined in  claim 1 , comprising:
 mixing each powder of Bi 2 O 3 , Bi, Cu and Te; and   sintering the mixed materials to manufacture the thermoelectric conversion materials.   
     
     
         8 . The method for manufacturing thermoelectric conversion materials according to  claim 7 ,
 wherein the sintering temperature is 400 to 570° C.   
     
     
         9 . A thermoelectric conversion device including the thermoelectric conversion materials defined in  claim 1 .