Charge Transport Regulation in Solution-Processed OLEDs by Indenocarbazole-Triazine Bipolar Host Copolymers.

This work reports the synthesis of a series of bipolar host polymers, specifically , , and , which incorporate a hole-transporting unit, 7,7-dimethyl-5-phenyl-2-(4-vinylphenyl)-5,7-dihydroindeno[2,1-]carbazole , and an electron-transporting unit, 2,4-diphenyl-6-(4-vinylphenoxy)-1,3,5-triazine . These polymers are meticulously designed to achieve efficient bipolar charge transport while exhibiting high triplet energy levels (T), robust thermal stability, and smooth surface morphology. The tunability of the recombination zone position was achieved by adjusting the relative ratio of the hole and electron transport units in the emissive layer, leading to optimized charge balance and enhanced device performance.

Well-Balanced Ambipolar Charge Transport of Diketopyrrolepyrrole-Based Copolymers: Organic Field-Effect Transistors and High-Voltage Logic Applications.

A poly (3,6-bis(thiophen-2-yl)-2,5-bis(2-decyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione-co-(2,3-bis(phenyl)acrylonitrile)) (PDPADPP) copolymer, composed of diketopyrrolopyrrole (DPP) and a cyano (nitrile) group with a vinylene spacer linking two benzene rings, is synthesized via a palladium-catalyzed Suzuki coupling reaction. The electrical performance of PDPADPP in organic field-effect transistors (OFETs) and circuits is investigated. The OFETs based on PDPADPP exhibit typical ambipolar transport characteristics, with the as-cast OFETs demonstrating low field-effect hole and electron mobility values of 0.