Fused Heptacyclic-Based Acceptor–Donor–Acceptor Small Molecules: N-Substitution toward High-Performance Solution-Processable Field-Effect Transistors

Abstract

Although various donor−acceptor (D−A) small molecules with high power conversion efficiency have been reported, D−A small molecules with high field-effect mobility are still rare. In this work, two new A−D−A small molecules with a rigid indacenodithieno[3,2-b]thiophene (IDTT) moiety as the central core and both ends capped with strong electron-withdrawing indole-2,3-dione (IDD) and N-substituted pyrrolo[2,3-b]pyridine-2,3-dione (IDD-N) were synthesized and characterized for applications in solution-processable organic field-effect transistors (OFETs). A N atom was introduced to the IDD units to enhance the planarity and structural ordering by noncovalent interactions, leading to a dramatic effect on the small molecule. The unsubstituted small molecule (IDTT−IDD) did not show any field-effect performance, whereas an encouraging hole mobility of 7.7 cm 2 V −1 s −1 with an average mobility of 6.1 cm 2 V −1 s −1 was obtained for solution-processable OFETs based on the Nsubstituted one (IDTT−IDD-N). This work provided a simple and effective molecular strategy for the design of D−A small molecules for high-performance solution-processable OFETs.

Universal three-dimensional crosslinker for all-photopatterned electronics

“…olution-processed electronics have been considered a disruptive technology rooted in cost-effective manufacturing [1][2][3][4][5][6][7][8] . The performance of electronic devices based on various solution-processable materials, such as polymer semiconductors, organic small molecules, and nanostructured materials, is being improved continually 6,[9][10][11][12][13][14][15] . However, fabrication of these devices entirely through a series of solution processes remains highly challenging, as they comprise a stack of fully patterned electronic components, such as electrode layers, charge transporting interlayers, active channel layers, and insulating layers.…”

Thieno[3,2-b]pyrrole and Benzo[c][1,2,5]thiadiazole Donor–Acceptor Semiconductors for Organic Field-Effect Transistors

“…Design of novel OSCs with improved performance in devices is a demanding challenge. Design strategies include the use of fused rings, 15,18 side-chain engineering, 19−21 positioning of donor and acceptor (D–A) units, 22,23 and heteroatom replacement in the conjugated backbone. 8,15 Among them, the inclusion of fused rings in the backbone and D–A structural designs are widely studied to tailor their optoelectronic properties.…”

“…Design strategies include the use of fused rings, 15,18 side-chain engineering, 19−21 positioning of donor and acceptor (D–A) units, 22,23 and heteroatom replacement in the conjugated backbone. 8,15 Among them, the inclusion of fused rings in the backbone and D–A structural designs are widely studied to tailor their optoelectronic properties. Fused rings systems permit the formation of more rigid and planer assemblies, forming more favorable π–π intermolecular interactions with the deep-lying HOMO energy level through larger resonance stabilization energy, resulting in better charge carrier transport characteristics.…”

“…Fused rings systems permit the formation of more rigid and planer assemblies, forming more favorable π–π intermolecular interactions with the deep-lying HOMO energy level through larger resonance stabilization energy, resulting in better charge carrier transport characteristics. 15,18,24 Thieno[3,2- b ]thiophene, 25,26 4 H -dithieno[3,2- b :2′,3′- d ]pyrrole, 27,28 benzo[1,2- b :4,5- b ′]difuran, 29,30 and benzo[1,2- b :4,5- b ′]dithiophene 30,31 are some of the fused rings extensively explored to generate OSC constructs. Similarly, designing small molecules with D–A architecture increases the intermolecular interactions originated from donor and acceptor moieties, aiding in the production of high-performing OSC devices.…”

Aza-Based Donor-Acceptor Conjugated Polymer Nanoparticles for Near-Infrared Modulated Photothermal Conversion

“…On the one hand, the introduction of electronegative N atom could further enhance the electron-withdrawing power of acceptor which result in strong push-pull interaction and significant red-shifts of absorption (Zhang et al, 2017a). On the other hand, the N-substitution on backbone can produce non-covalent interaction (S…N and CH….N) and endows the polymer with improved planar structure, which can also lead the redshift of absorption (Jackson et al, 2013; Zhang et al, 2019). Because of the hydrophobic conjugated polymers, it is difficult to further apply to living organisms, conjugated polymer-based NPs were prepared by using amphiphilic diblock copolymer poly(ethylene glycol)-block-poly(hexyl ethylene phosphate) (mPEG-b-PHEP) as the stabilizer using the single emulsion method.…”