Lattice distortion and thermoelectric property for Zn_1-(x+y)Ga_xIn_yO system (x + y = 0.007, 0≤x≤0.007, 0≤y≤0.007)

Abstract

The intermetallic compounds which are mainly used for the thermoelectric power generation system are unstable at high temperature. Therefore, we studied thermoelectric property of ZnO doped with group 3B elements periodic table, which can be expected to be a good candidate of thermoelectric material with high performance. The electrical conductivity (σ) and See beck coefficient (S) were evaluated under He atmosphere from 673 to 1073K. Although the electrical conductivity was showed maximum value for sample with r_av. = 0.054 nm, the Seebeck coefficient did not change for all samples. This fact was considered that the increase in electrical conductivity was caused by improvement of carrier mobility, and the improvement of carrier mobility may be ascribed to the decrease in lattice distortion which caused by co-doping. Power factor (S²σ) of Zn_9.993Ga_0.0023In_0.0047O showed higher value than that of Zn_9.993A_0.007O (A = Ga, In). Thus, the co-doping was effective for the improvement of power factor.