High-Temperature Thermoelectric Properties of Compounds in the System Zn x In y O x+1.5y

Based on results obtained utilizing combinatorial chemistry techniques to screen the thermoelectric power factor of materials in the system ZnxIny Ox+1.5y, several multiphase candidates were down-selected and investigated in terms of their thermoelectric response from room temperature to 1050°C. While the screening experiments suggested that peaks in the power factor occur at relatively high indium oxide content, only the thermoelectric properties of zinc-oxide-rich homologous layered phases in the system (In2O3)(ZnO)k have been well documented, since the phases where k < 3 cannot be easily formed. In the present study, indium-oxide-rich materials in the system In2O3–(In2O3)(ZnO)3 were fabricated and their figures of merit were determined. The results suggest that the indium-oxide-rich phases have improved figures of merit, especially at elevated temperatures, relative to the best performing k phases by combining the high power factor of In2O3 and the low thermal conductivity of (In2O3)(ZnO)k.