Luminescence Behavior And Acceptor Effects Of Ambipolar Polymeric Electret On Photorecoverable Organic Field-Effect Transistor Memory

Photorecovery systems are considered to be a potential technology in photosensor, green energy-saving, and high-speed communication applications (light-fidelity). However, the role of photoactive-electret and semiconductor in the photorecovery system is still unintelligible. Herein, triphenylamine (TPA)-based donor-acceptor polymers are designed as electrets with more effective excitons dissociation for organic field-effect transistor memory equipped with photosensitive and photorecoverable response. By modifying TPA-derived conjugated polymers with various electron-withdrawing groups (PTPA-CN, PTPA-CNBr, and PTPA-3CN), the obtained PTPAs induce disparate luminescent behaviors in the aggregated state. PTPA-CN and PTPA-CNBr exhibit aggregation-induced emission (AIE) featuring the energy dissipation of partial photoexcited excitons through radiation, while PTPA-3CN turns to aggregation-caused quenching (ACQ) behavior leading considerable number of nonemissive excitons which can directly recombine with charged medium, an electret containing trapped charges. Pentacene-based transistor devices incorporated with studied photoactive electrets are constructed for mechanism investigation. The results demonstrate that photorecovery response ability of ACQ-polymer displays much faster than that of AIE-polymers, PTPA-CN, and PTPA-CNBr, upon UV light irradiation, attributing to the intensely electron-withdrawing ability of acceptor attached on the conjugated skeleton. The ACQ-electret device behaves superior memory switching performance with reliable endurance characteristics under the cycling stress of electrical-programming and optical-erasing operations, demonstrating the feasibility for organic optoelectronic applications.