在ITO玻璃上制备了ITO/poly（3,4-ethylene dioxythiophene）∶poly（styrene sulphonate）（PEDOT∶PASS）/poly （N,N-bis（4-butylphenyl）-N,N-bis（phenyl）benzidine（poly-TPD）/QD/1,3,5-Tri（1-phenyl-1H-benzo[d]imidazol-2-yl） phenyl（TPBi）/LiF/Al结构的量子点发光二极管（QD-LED）。通过优化量子点的浓度,发现浓度为30 mg/mL时的器件性能最优,最大外量子效率（EQE）为0.83%,最大发光亮度为4076 cd/m2。为了进一步提高QD-LED的发光效率,将QD掺入聚合物poly（N-vinylcarbazole）（PVK）和1,3-Bis（5-（4-（tert-butyl）phenyl）-1,3,4-oxadiazol-2-yl）ben-zene （OXD-7）中,以使得注入的电子和空穴更加平衡,同时还有助于能量传递,降低QD团聚及修饰QD薄膜表面,减少激子猝灭效应等。为此,通过旋涂和蒸镀两步法制备ITO/PEDOT∶PASS/poly-TPD/（PVK∶OXD-7）∶QD/TPBi/LiF/Al结构的器件,改变（PVK∶OXD-7）∶QD比例（1∶1,1∶3,1∶5,0∶1）,发现（PVK∶OXD-7）∶QD为1∶3时的QD-LED具有最优性能,最大EQE为1.97%,相当于非掺杂器件的2.3倍,并且发光峰没有发生偏移。%Quantum dot light-emitting diodes ( QDLED ) with structure ITO/poly ( 3 , 4-ethylene dioxythiophene)∶poly(styrene sulphonate) (PEDOT∶PASS)/poly(N,N-bis(4-butylphenyl)-N,N-bis ( phenyl ) benzidine ( poly-TPD )/QD/1 , 3 , 5-Tri ( 1-phenyl-1 H-benzo [ d ] imidazol-2-yl ) phenyl ( TPBi)/LiF/Al were fabricated. By optimizing the concentration of quantum dots, maximum exter-nal quantum efficiency ( EQE) of 0. 83% and maximum emission luminance of 4 076 cd/m2 were achieved at a QD concentration of 30 mg/mL. In order to further improve the efficiency of QDLED, QDs were doped into polymer poly(N-vinylcarbazole) (PVK) and 1,3-Bis(5-(4-(tert-butyl)phen-yl)-1,3,4-oxadiazol-2-yl)benzene (OXD-7) so as to balance the injection of electrons and holes, reduce the aggregation of QDs and improve the surface of the films. Devices with structure ITO/PE-DOT∶PASS/poly-TPD/( PVK∶OXD-7 )∶QD/TPBi/LiF/Al were fabricated by spin coating and ther-mal evaporation. By optimizing the doping concentration of QDs, the maximum EQE of 1. 97% is obtained, which is 2. 3-fold higher than that of the undoped devices.
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