Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China.
ACS Appl Mater Interfaces. 2018 Apr 4;10(13):11377-11381. doi: 10.1021/acsami.8b01758. Epub 2018 Mar 23.
The cathode interlayer is of crucial importance for efficient electron injection in inverted polymer light-emitting diodes (PLEDs) to realize high electroluminescence efficiency. Here, a novel photoconductive cathode interlayer based on organic dye-doped ZnO (ZnO:PBI-H) is applied as the cathode buffer layer in PLEDs, and dramatically enhanced device performance is obtained. The photodoping of ZnO may greatly promote the electron injection ability under the device working conditions, which increases the electron-hole recombination efficiency when using P-PPV as the light-emitting material. Thanks to the decreased energy barrier between the cathode interlayer and the light-emitting layer, the turn-on voltage of the PLEDs is obviously reduced when using the photoconductive cathode interlayer. Our results indicate that photodoping of the cathode interlayer is a promising strategy to increase the interlayer performance in light-emitting diodes.
对于实现高效率电致发光的倒置聚合物发光二极管（PLED），阴极中间层对于高效电子注入至关重要。在此，将基于有机染料掺杂 ZnO（ZnO：PBI-H）的新型光导阴极中间层用作 PLED 的阴极缓冲层，从而获得了显著增强的器件性能。ZnO 的光掺杂可能会极大地促进器件工作条件下的电子注入能力，从而提高使用 P-PPV 作为发光材料时的电子-空穴复合效率。由于阴极中间层和发光层之间的能垒降低，使用光导阴极中间层时 PLED 的开启电压明显降低。我们的结果表明，阴极中间层的光掺杂是提高发光二极管中间层性能的一种很有前途的策略。
