Achieving High zT with Carbon Nanotube/Conjugated Microporous Polymer Thermoelectric Nanohybrids by Meticulous Molecular Geometry Design

Abstract Conjugated microporous polymers (CMPs) are characterized by high physical and chemical stabilities along with low thermal conductivities due to their conjugated microporous frameworks, making them promising candidates for thermoelectric application. However, the advancement of CMPs within the thermoelectric field is considerably hampered by their inadequate electrical conductivity and unfavorable processability. Herein, highly‐conducting carbon nanotubes (CNTs) are dispersed in two solvents (1,2‐dichlorobenzene and N‐methyl‐2‐pyrrolidone) to fabricate p‐ and n‐type CNT/CMP nanohybrids. Additionally, two unique CMPs are synthesized to elucidate the impacts of the chemical structures and pore architectures on the thermoelectric properties of the nanohybrids. Finally, due to the differing steric hindrance effects of the two CMPs, the thermoelectric performance can be tuned under varying circumstances. The synergetic effects of low thermal conductivity and efficient dispersion capability of the CMPs yield optimized figure of merit (zT) values of 0.053 and 0.13 at 303 K for the p‐ and n‐type thermoelectric nanohybrids, respectively. This investigation presents an alternative approach to building high zT p‐ and n‐type thermoelectric CNT/CMP nanohybrids operating near ambient temperature via the solvent doping effect and chemical structure design of the CMPs, thereby establishing CMP‐based materials as promising candidates for thermoelectric application.