We present a comprehensive model to analyze, quantitatively, and predict the process of degradation of organic light-emitting diodes (OLEDs) considering all possible degradation mechanisms, i.e., polaron, exciton, exciton-polaron interactions, exciton-exciton interactions, and a newly proposed impurity effect. The loss of efficiency during degradation is presented as a function of quencher density, the density and generation mechanisms of which were extracted using a voltage rise model. The comprehensive model was applied to stable blue Cn An J J t represent the electron current densities at the cathode and anode sides L10 Aged Fresh *A/F fold : Mass intensity ratio between L10 aged pixel and fresh pixel. inf. = infinity, absent in fresh pixel.

This study was primarily focused on the preparation and characterization of conducting polymer=metal nanocomposites. Poly(3,4-ethylenedithiathiophene) was prepared onto ITO electrodes as thin film shapes by electrochemical polymerization and reduced with constant potential. When the polymer films were doped with K 2 PtCl 6 solution, they were easily get oxidized due to the concurrent reduction of Pt(IV) to Pt(0). This procedure ended up with the formation of polymer=metal composites. In-situ spectroelectrochemistry was used to investigate the composite formation processes. The final composites were indentified with SEM and EDAX. Catalytic decomposition of methanol on these composite electrodes was observed by using cyclic voltammetry.

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To utilize thermally activated delayed fluorescence (TADF) technology for future displays, it is necessary to develop host materials that can harness the full potential of blue TADF emitters. We suggest an elaborative approach for designing host molecules for blue TADF devices with simultaneously improved efficiency and stability. We significantly enhanced the delayed fluorescence quantum yield by engineering the molecular geometry, polarity, and excited-state dipole moment of host molecules based on 3′,5-di(9H-carbazol-9-yl)-[1,1′-biphenyl]-3-carbonitrile. The engineerd hosts stabilized the charge-transfer excited states of TADF emitters, suppressed exciton quenching, and improved the charge balance in the emitting layer. Moreover, because the hosts are phosphine-oxide bond-free molecules, they are photochemically and electrochemically stable compared to bis[2-(diphenylphosphino)phenyl] ether oxide, the most popular high-polarity host. The devices employing the hosts exhibited a two-fold increase in external quantum efficiency and a 37-fold increase in operation lifetime compared to control devices with the same TADF emitter.