Thienothiophene based organic light-emitting diode: synthesis, photophysical properties and application

Abstract

A donor-p-acceptor (D–p–A) type pull–push compound, DMB-TT-TPA, of triphenylamine as a donor and dimesitylboron as an acceptor, linked through a thieno[3,2-b]thiophene (TT) p-conjugated linker bearing 4-MeOPh group, was designed, synthesized and fabricated as an emitter via a solution process for an organic light-emitting diode (OLED) application. DMB-TT-TPA exhibited absorption and emission maximums of 411 and 520 nm, respectively, with a mega Stokes shift of 109 nm and fluorescence quantum yields both in solid-state (41%) and in solution (86%). The optical properties were supported by computational chemistry using density functional theory for optimized geometry and absorption. A solution-processed OLED was fabricated using low turn-on voltage, which had performances with maximum power, current and external quantum efficiencies of 6.70% lm.W-1, 10.6 cd.A-1 and 4.61%, respectively.