Li Dingxin,Liu Hongli,Rungo Basílio Alberto,Li Xianggao,Wang Shirong
Solution-processed Organic light-emitting diodes (OLEDs) have aroused serious attention because of its lower cost and easier fabrication. Herein, a novel triazine-based molecular emitter is reported for solution-processed OLEDs for the first time. The emitter, 4,4′,4′'-(1,3,5-triazine-2,4,6-triyl)tris(N,N-bis(4-(3,6-di-tert-butyl-9H-carbazol-9-yl)phenyl)aniline) denoted as Tri-2tCzPA-TRZ, shows excellent solubility in common organic solvents, facilitating solution-processed OLEDs. The resultant OLEDs doped with 1,3-di(9H-carbazol-9-yl)benzene (mCP) achieved a maximum current efficiency of 18.8 cd A −1 and maximum luminance of 12,580 cd m −2 , which is higher than the maximum current efficiency of the most solution-processed OLEDs in simple structures.
The development of cadmium-free blue quantum dots (QDs) is of paramount importance to the display industry. In this study, high-quality ZnSeTe/ZnSe/ZnS blue QDs, followed by surface treatment with ZnI 2 are initially synthesized. The introduction of ZnI 2 passivated the surface defects, resulting in an increase in the fluorescence quantum yield. The time-resolved photoluminescence (TRPL) demonstrates a significant inhibition of non-radiative recombination associated with the surface defect state. The density functional theory (DFT) calculation reveals that the binding energy between iodine ions and zinc ions is higher than that between oleate ions and zinc ions, providing a theoretical basis for the effective passivation of the suspended bonds of zinc ions on QDs' surface by iodine ions. Moreover, quantum dot light-emitting diodes (QLEDs) are fabricated and UV photoelectron spectra (UPS) indicate the hole injection barrier between the hole transport layer and QDs decreases 0.12 eV after QDs being treated by ZnI 2 , facilitating hole injection. Finally, The ZnI 2 -treated QLED demonstrates a 1.57-fold and 1.82-fold improvement in L max and EQE max , respectively, reaching 6370 cd m −2 and 9.1%, compared to the pristine QLED. The work serves as a valuable reference for enhancing the performance of cadmium-free blue QLED.
危险品化学品经营许可证（带存储）