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采用真空蒸镀的方法,制备了以ADN为发光层的高效率非掺杂蓝色有机电致发光器件.器件的结构为ITO/2T-NATA(15 nm)/NPBx(15 nm)/ADN(25+d nm)/BCP(8 nm)/ Alq_3(30 nm)/LiF(0.5 nm)/Al.通过调整ADN层的厚度,研究了器件的发光性能.测试结果表明,器件在6 V电压时电流效率达到最大,为2.77 cd/A;在16 V时亮度达到最大,为7 227 cd/m~2.当ADN的厚度为30 nm、器件的电压从5 V变化到16 V时,色坐标在(0.21,0.32)至(0.19,0.29)之间,均在蓝光区域.Abstract: Using ADN as the emitting layer, high efficient undoped blue organic light-emitting diodes(OLEDs) with a typical structure of (ITO)/ 2T-NATA(15 nm)/ NPBx(15 nm)/ ADN(25+d nm)/BCP(8 nm)/Alq_3 (30 nm)/LiF(0.5 nm)/Al were fabricated via thermal vacuum deposition method. This device has a maximum luminous efficiency of 2.77 cd/A at 6 V and maximum luminance of 7 227 cd/m~2 at 16 V. The CIE coordinates of the device are within the blue region when the thickness of ADN is 30 nm and the voltage changes among the range of 6~16 V. 相似文献
23.
与液晶显示器(LCD)相比,有机发光二极管显示器(organic light emitting display,OLED)具有主动发光、广视角、重量轻、厚度小、高亮度、高发光效率、发光材料丰富、易实现彩色显示、响应速度快、动态画面质量高、使用温度范围广、可实现柔软显示、工艺简单、成本低、抗震能力强等一系列优点,因此被专家称为未来的理想显示器。文章介绍了OLED的产生与发展过程,并着重介绍了OLED与目前占主导地位的LCD和等离子显示器(PDP)相比在显示性能和器件制造方面所具有的领先优势。 相似文献
24.
制备了以Zn(BTZ)2∶rubrene为发光层的5种白色有机电致发光器件,并将其应用于液晶显示背光源。5种器件色度最好时的CIE坐标值为(0.32,0.33),最大有效发光面积达到3 cm×3 cm,此时器件的平均亮度达到264 cd/m2,亮度均匀性达到80%。并且分析了随器件有效发光面积增大,发光均匀性、亮度以及最大量子效率减小而器件电流密度反而增大的原因。同时发现附加金属(Ag)辅助电极在一定程度上有助于提高器件的性能。最后将所制备的5种器件与液晶显示屏相匹配,它们均基本满足液晶显示对背光源的要求。 相似文献
25.
提出一种以聚合物MEH PPV为发光材料,结构为Al/MEH PPV/CuPC/ITO的倒置型发光器件(I PLED)。对既是空穴传输层又是轰击缓冲层的CuPC厚度以及MEH PPV的浓度对器件性能影响的分析发现,在实验条件下,最佳的CuPC厚度约为3.5nm,最佳的MEH PPV浓度约为3‰;采用小分子染料红莫稀(Rubrene)对聚合物发光材料MEH PPV掺杂发现,器件的亮度从未掺杂的40 4cd·m2提高到掺杂后的207.7cd/m2,其发光峰从未掺杂的624nm蓝移到掺杂后的592nm,但其I V特性并没有明显的变化。 相似文献
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Brightly luminescent and highly soluble lanthanide tetrafluorobenzoates, as well as their mixed ligand complexes, were synthesized and thoroughly characterized. The low charge carrier mobility hampered their use in OLED, but this problem was overcome by a thoughtful selection of host material. The organic molecules acted both as ligands in the complex and as the host material, leading to zero increase in the Stokes shift. 相似文献
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A series of side-chain polystyrenes was developed as ambipolar hosts for solution processed organic light emitting diodes (OLEDs). The series was derived from the hole-only transport host molecule 1,3-Bis(N-carbazolyl)benzene (mCP). Electron transport ability was incorporated into the host polymers by the introduction of electron-poor heterocycles (pyridine or triazine) and extending delocalization of the lowest unoccupied molecular orbital (LUMO). The materials were tested in Ir-based green OLED devices with all organic layers processed from solution. Devices with the polymer combining triazine and carbazole on its side-chain exhibited a low luminance on-set voltage of 3.0 V and a current efficacy of 28.9 cd/A, which was more than 10 times higher than for devices with the mCP-based polymer (1.6 cd/A). The increase in performance is most likely due to an improvement of charge balance in the emissive layer, showing that our ambipolar polymers are good candidates for further wet-process optoelectronic applications. 相似文献
30.
Solution-processed organic light-emitting devices (OLEDs) still require improvements in their operational lifetime in order for them to become commercially viable. One factor that limits the lifetime of these devices is the instability of the hole injection layer (HIL). Therefore, understanding its degradation mechanism is crucial for the development of more stable solution-processed OLEDs. In this work, we use an archetypal fluorescent OLED in conjunction with an experimental solution-processed HIL in order to elucidate the degradation mechanism in these HILs. Our studies show that degradation is caused by triplet excitons. This new triplet-induced hole injection degradation is expected to be a common phenomenon in OLEDs, and therefore should have important implications for the design of stable HILs. 相似文献