ICT2014 Abstracts

Thermoelectric devices have received much attention due to recovering electrical energy from waste heat, consequently improving the global energy consumption efficiency. The PbTe-based compounds have been extensively used for thermoelectric power generation at the medium temperature range between 500 and 800 K. In this study, nano-structures incorporation and carrier concentration optimization were utilized to enhance the thermoelectric properties of n-type PbTe. Bi and transition metal dopants were added to PbTe and the samples were variously heat treated. ZT values ranged from 0.9 to 1.3 at 673K, depending on compositions of the samples. Interestingly, the peak ZT value at the specific temperature and the averaged ZT value with respect to temperature were separately controlled with designing the composition. The averaged ZT ranging from root temperature to 673 K was about 0.74. The developed materials and thermoelectric properties were found as reproducible and having mechanically processability. The first-principles calculation were also studied to understand effect of each dopant on the thermoelectric properties.