High temperature thermoelectric properties of Ca1-xBixMn1-yVyO3-delta (0 <= x=y <= 0.08)

CaMnO3-delta with complex additives Bi2O3-V2O5 were prepared by the solid-state reaction. The crystal structures of the Ca1-xBixMnt-yVyO3-delta (0 <= x=y <= 0.08) solid solutions were determined by means of the powder X-ray diffraction (XRD) using Rietan 2000 program and the high temperature thermoelectric properties were also investigated. Perovskite-type Ca1-xBixMn1-yVyO3-delta solid solutions are n-type semiconductors. The lattice parameters increase with increasing dopant level. The high temperature thermoelectric properties are improved due to Bi2O3-V2O5 simultaneous doping. A maximum ZT value reaches to 0.21 for electron-doped Ca(0.96)Bi(0.04)Mn(0.96)V0.04O(3-delta) at 1050 K, which is about twice as high as that of CaMnO3-delta. The thermal shock resistance at temperatures between 20 and 450 degrees C is also highly improved. (c) 2007 Elsevier Ltd. All rights reserved.