The Impact of Topological States on the Thermoelectric Performance of p- and n-Type SbTe/BiSe-Multiwalled Carbon Nanotubes Heterostructured Networks

The resistance and magnetoresistance of flexible thermoelectric p-type SbTe-MWCNT, p-type BiSe-MWCNT, and n-type BiSe-MWCNT heterostructures were studied in the temperature range from 2 K to 300 K to reveal the conductance mechanisms governing the thermoelectric properties of these heterostructured networks. It was found that the conductance in heterostructured networks at different temperatures is governed by different processes and components of the networks. This effect was found to be related to the growth mechanisms of the SbTe and BiSe nanostructures on the MWCNT networks. At near-room temperatures, the SbTe and BiSe nanostructures were found to have the dominant contribution to the total conductance of the p-type SbTe-MWCNT and n-type BiSe-MWCNT networks. In turn, the conduction of p-type BiSe-MWCNT heterostructured networks in a full temperature range and p-type SbTe-MWCNT and n-type BiSe-MWCNT heterostructured networks at temperatures below 30 K was governed by the MWCNTs; however, with the contribution from 2D topological states of SbTe and BiSe nanostructures, these were manifested by the weak antilocalization effect (WAL) cusps observed at temperatures below 5–10 K for all heterostructured networks considered in this work.