Freestanding Polymer Assembly Conductor by Contact-Free Annealing

Abstract

Molecular chain ordering and geometrical confinement of conjugated polymers determine the structural and electronic activity of entire organic systems. Here, we present a surface-tension induced spontaneous formation of freestanding conjugated polymer nanosheets followed by a contact-free annealing treatment to achieve the optimum crystallization and conductivity. Nanoconfinement in macroscopic crystalline polymer nanosheets produces mechanical robustness and high mobility. The conductivity of freestanding nanosheets displays an increase of 3 orders of magnitude from 4.2 × 10–3 to 5.5 S cm–1 through halogen induced charge-transfer interactions. Meanwhile, the densely compacted and freestanding electronic-active polymer nanosheets open up the route for thermal energy conversion with the output thermovoltage of 16.93 mV K–1.