PUB-2013-HTT

High Temperature Thermoelectric Properties of Nb-doped and Oxygen Vacancy-doped SrTiO3

S.R.S. Kumar, Abeer Barasheed, and H.N. Alshareef, “High Temperature Thermoelectric Properties of Nb-doped and Oxygen Vacancy-doped SrTiO3”
ACS Appl. Mater. Interfaces, 20135 (15), pp 7268–7273
S.R.S. Kumar, Abeer Barasheed, and H.N. Alshareef
thermoelectrics; oxide semiconductors; transport properties; pulsed laser deposition; oxygen vacancies
2013
We report the evolution of high temperature thermoelectric properties of SrTiO3 thin films doped with Nb and oxygen vacancies. Structure–property relations in this important thermoelectric oxide are elucidated and the variation of transport properties with dopant concentrations is discussed. Oxygen vacancies are incorporated during growth or annealing in Ar/H2 above 800 K. An increase in lattice constant due to the inclusion of Nb and oxygen vacancies is found to result in an increase in carrier density and electrical conductivity with simultaneous decrease in carrier effective mass and Seebeck coefficient. The lattice thermal conductivity at 300 K is found to be 2.22 W m–1 K–1, and the estimated figure of merit is 0.29 at 1000 K.