Phthalimide-Based Polymers for High Performance Organic Thin-Film Transistors

Abstract

The synthesis and characterization of two new thiophene copolymers with backbone phthalimide units is reported. Thin-film optical and wide-angle X-ray diffraction measurements indicate extended electronic conjugation and close intermolecular pi-stacking for both polymers. Ambient carrier mobility of thin-film transistors prepared from these polymers is as high as 0.28 cm(2)/(V s) with an on/off ratio greater than 10(5).

High‐mobility Ambipolar Transistors and High‐gain Inverters from a Donor–Acceptor Copolymer Semiconductor

“…NBI-based copolymers have so far proved to be good n-channel transistor materials, [32,33] and the incorporation of the highly electron-rich dialkoxybithiophene is expected to enhance p-channel charge-transport. [34] PNIBT was effectively synthesized by Stille coupling polymerization using Pd 2 (dba) 3 /P(o-tolyl) 3 as catalyst, similar to our previous report for a related analogue. [35] The molecular weight of PNIBT, determined by gel permeation chromatography relative to polystyrene standards, was 113 kDa with a polydispersity index of 3.33.…”

“…The highly entangled nanostructures seen in the surface morphology of PNIBT thin films, in addition to the local ordering of the polymer as indicated from optical absorption and XRD spectra, appear to facilitate domain interconnectivity essential to high charge-carrier mobility, similar to recent observations in other high-mobility polymers. [34,38,39] We have successfully used the ambipolar PNIBT transistors fabricated and integrated on a common substrate to demonstrate complementary inverters. An inverter consists of two connected transistors and enables the switching of an input signal (e.g., V in ) to an output signal (e.g., V out ), and is thus a valuable building block of digital circuits for data processing.…”

Communication: Tailoring the optical gap in light-harvesting molecules

“…This strategy has been successfully utilized to harvest the solar spectrum efficiently. [22][23][24] Polymers based on NDI and thiophene units are known compounds for the use as electron acceptor (n type) materials. 0.8 cm 2 /Vs in organic field effect transistors.…”

Semi-crystalline A1–D–A2-type copolymers for efficient polymer solar cells

“…Two solubilizing alkoxy side chains at the 5-and 6-positions of BTz induce intra-and/or interchain coulombic interactions via S δ+ -O δ − between the oxygen and sulfur atoms in the neighboring thiophene and BTz moieties. 38,39 The BT moiety is used as the main acceptor, with fluorine atoms at the 5-and 6-positions to modulate the frontier orbital levels and oxidational stability of the resulting polymers. 40,41 This design is expected to yield both a low band gap and a deep HOMO level.…”