We propose a strategy for enhancing thermoelectric performance through the realization of a 'phonon-glass electron-crystal' (PGEC) by interface control using multiwalled carbon nanotubes (MWCNTs). By the consolidation of undoped ZnO nanoparticles with MWCNTs (0.5, 1, and 2 wt%) using spark plasma sintering, we fabricated the interface-controlled ZnO-MWCNT nanocomposites, in which ZnO grains were surrounded with a MWCNT network. Both single crystal-like charge transport (electron-crystal) and considerably reduced thermal conductivity (phonon-glass) were achieved simultaneously thanks to the beneficial effects of the MWCNT network, and this led to the enhancement of the thermoelectric figure of merit. We discussed these findings on PGECs in the ZnO-MWCNT nanocomposites from the viewpoint of interface control in detail, and our strategy may provide a promising way to the realization of PGEC in other hybrid thermoelectric materials.
Bibliographical noteFunding Information:
This work was supported by IBS-R004-D1 and also by the Mid-career Researcher Program (2015R1A2A2A01005929) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology, Republic of Korea.
All Science Journal Classification (ASJC) codes
- Materials Science(all)