MoS2 Assisted Self-Assembled Poly(3-hexylthiophene) Thin Films at an Air/Liquid Interface for High-Performance Field-Effect Transistors under Ambient Conditions

Abstract

It is a key challenge to achieve long-range ordering in the nanoscale morphology of π-conjugated polymers for efficient charge transport in organic electronic devices. The long-range ordering and aggregation in poly(3-hexylthiophene) (P3HT) have been accomplished by introducing two-dimensional (2D) molybdenum disulfide (MoS2) nanosheets to a polymer matrix, followed by ultrasonication in chloroform. Thin films of synthesized P3HT/MoS2 nanocomposites, having various fractions of MoS2 in the P3HT matrix, have been fabricated on the air/liquid interface. UV-vis absorption spectroscopy has been employed to investigate the nature of aggregation and exciton bandwidth in the resultant films deposited at the air/liquid interface. Moreover, grazing incidence X-ray diffraction (GIXD) analysis and atomic force microscopy (AFM) reveal the long-range ordering and highly crystalline thin films with the edge-on orientation of polymer chains over the substrate. Furthermore, the impact of aggregation, morphology, and orientation on macroscopic charge transport performance is elaborately estimated by fabricating organic field-effect transistors (OFETs). A hole mobility as high as 0.160 ± 0.007 cm2 V-1 s-1 has been achieved for a P3HT/MoS2 (1%) nanocomposite under ambient conditions. © 2020 American Chemical Society.