Achieving High Performance Stretchable Conjugated Polymers via Donor Structure Engineering

Abstract

A backbone engineering strategy is developed to tune the mechanical and electrical properties of conjugated polymer semiconductors. Four Donor–Acceptor (D–A) polymers, named PTDPPSe, PTDPPTT, PTDPPBT, and PTDPPTVT, are synthesized using selenophene (Se), thienothiophene (TT), bithiophene (BT), and thienylenevinylenethiophene (TVT) as the donors and siloxane side chain modified diketopyrrolopyrrole (DPP) as acceptor. The influences of the donor structure on the polymer energy level, film morphology, molecular stacking, carrier transport properties, and tensile properties are all examined. The films of PTDPPSe show the best stretchability with crack‐onset‐strain greater than 100%, but the worst electrical properties with a mobility of only 0.54 cm2 V−1 s−1. The replacement of the Se donor with larger conjugated donors, that is, TT, BT, and TVT, significantly improves the mobility of conjugated polymers but also leads to reduced stretchability. Remarkably, PTDPPBT exhibits moderate stretchability with crack‐onset‐strain ≈50% and excellent electrical properties. At 50% strain, it has a mobility of 2.37 cm2 V−1 s−1 parallel to the stretched direction, which is higher than the mobility of most stretchable conjugated polymers in this stretching state.

Additive engineering for high-performance polythiophene gas sensors incorporating functional amine additive with strong binding energy for NO2

“…18 With incorporation of the additives, the hole-carrier density decreased, but the crystallinity of the P3HT film increased; therefore, it was confirmed that there was no significant change in the field-effect mobility. 36 To examine the gas sensing performance, gas sensor devices employing the films were exposed to 10 ppm NO 2 for 20 s and repeatedly purged with air for 200 s. The drain current (I d ) was measured over time at a gate voltage (V G ) and drain voltage (V D ) of À10 V (Fig. 3c).…”

Blends of Conjugated and Adhesive Polymers for Sticky Organic Thin‐Film Transistors

“…[46,47] For PDPP/PCS blends, the alkyl spacing distance increases from 19.6 Å up to 20.0 Å and the 𝜋-𝜋 stacking distance increases from 3.72 up to 3.77 Å. [48,49] In the PBTTT/PCS and P3HT/PCS systems, the addition of PCS causes some of the conjugated polymer chains to align in the face on orientation. For PBTTT/PCS blends, the in-plane alkyl spacing distance ranges from 22.0 to 22.8 Å, which is close to the out-of-plane alkyl spacing distance.…”

Comparative Investigation of Ultrafast Excited-State Electron Transfer in Both Polyfluorene-Graphene Carboxylate and Polyfluorene-DCB Interfaces

“…By virtue of their light harvesting properties, CPEs have also been utilized as photosensitizers in fluorescent sensors [9] and solar cells applications [7][8][9][10]. The basis of such successful utilization of the CPEs in the optoelectronic applications is their chemical structures which can be easily changed as well as their semiconducting properties with large optical densities [11,12]. In addition, their high emission intensities can be also one of their important features to be used for fluorescence resonance energy transfer [13,14].…”