Enhancement of Thermoelectric Figure of Merit of SrTi0.92R0.08O3 (R=Ta, Ho).

The thermoelectric properties of SrTi0.92R0.08O3 (R=Ta, Ho) were investigated using First principle approached in DFT. Quantum Espresso software are used together with BoltzTraP code which based on semiclassical Boltzmann transport theory to determine the thermoelectric properties at temperature range of 200K - 800K. In electronic properties calculation, density of state and partial density of state were analyzed. The doped element R influence the Fermi level position by crossing the conduction region causing samples becomes metallic in nature. STTO is p-type by nature while STHO is n-type. At room temperature the figure of merit (ZT) of 0.14 and 0.04 were recorded for STHO and STTO respectively. Maximum ZT of 0.35 were observed at 650K for STHO and 0.25 for STTO at 800K. Compared to previous work on Sr site doping, Ti site ZT result is relatively low. [ABSTRACT FROM AUTHOR]