Thermoelectric property studies on bulk TiOx with x from 1 to 2

100% dense bulk TiOx samples have been made by first oxidizing TiO and then direct current induced hot press. It was found that the Seebeck coefficients are negative at room temperature and change to positive at higher temperature for 1 < x < 1.25, positive at room temperature and change to negative at higher temperature for 1.25 < x < 5/3, and always negative up to 800 degrees C for 5/3 < x < 2. The highest achieved dimensionless figure of merit is about 0.2-0.23 for 1.83 < x < 1.9, about eight times lower than the reported value. (c) 2007 American Institute of Physics.