Transport properties of AgPb_(16)SbTe_(18) prepared by the inclusion of nano AgSbTe_2 into PbTe matrix

摘要

For the present investigation, AgPb_(16)SbTe_(18) material was prepared by the inclusion of AgSbTe_2 nanopowder into PbTe matrix, employing mechanical alloying route. This material was characterized for phase formation, microstructure, and transport properties. The microstructure showed densely populated grains with a grain size ~ 80 ran which plays an important role in controlling the transport properties. A remarkable enhancement in Seebeck coefficient (~ - 500 μV at 450 K) value of AgPb_(16)SbTe_(18) sample was observed which is attributed to the phonon scattering and the potential barrier, encountered by the charge carriers at the nanostructured grain boundaries. The other important findings are enhancement in electrical conductivity and reduction in thermal conductivity which directly enhance the figure of merit of the material and make it promising for thermoelectric power generator application in the mid-temperature zone.