Effects of Connecting Polymer Structure and Morphology at Inter‐Tube Junctions on the Thermoelectric Properties of Conjugated Polymer/Carbon Nanotube Composites

Abstract Conjugated polymer (CP)/carbon nanotube (CNT) composites have been actively used for thermoelectrics for more than a decade. Thermoelectric performance of CP/CNT composites is greatly improved compared with that of the individual components; however, the underlying origin of the performance improvement remains vague, without clear explanations at the molecular scale. Moreover, the nature of the heterogeneous system limits quantitative analysis and restricts physical understanding of the thermoelectric effect in the composites. By combining experimental approaches with molecular dynamics simulations, the contribution of the CPs to the thermoelectric properties at inter‐tube junctions between adjacent CNTs is revealed. Indacenodithiophene‐ co ‐benzothiadiazole (IDTBT), which has a highly planar backbone and does not aggregate at CP/CNT interfaces, can better mediate effective intr…