Effect of tunneling on the thermoelectric efficiency of bulk nanostructured materials

The possibility of increasing the thermoelectric figure of merit for bulk nanostructured materials has been investigated theoretically. The kinetic coefficients of the nanostructured material have been calculated and evaluated under the assumption that the dominant role in the transfer is played by the tunneling of electrons between nanoparticles. The limiting case of the absence of phonon thermal conductivity through barrier layers has been considered. It has been demonstrated using the estimates obtained for materials based on Bi2Te3 that the thermopower in the nanostructured material can be sufficiently high and that, despite the low electrical conductivity, the dimensionless thermoelectric figure of merit can be as large as 3-4 at room temperature.