Yang Kaiyu, Weng Xukeng, Feng Jiahuan, Yu Yongshen, Xu Baolin, Lin Qiuxiang, Zhang Qingkai, Zhuang Jiaqing, Hou Wenjun, Yan Xiaolin, Hu Hailong, Li Fushan
College of Physics and Information Engineering, Fuzhou University, Fuzhou 350108, People's Republic of China.
Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou 350108, People's Republic of China.
ACS Appl Mater Interfaces. 2024 Feb 21;16(7):9544-9550. doi: 10.1021/acsami.3c18371. Epub 2024 Feb 12.
Quantum dot light-emitting diodes (QLEDs) have attracted increasing attention due to their excellent electroluminescent properties and compatibility with inkjet printing processes, which show great potential in applications of pixelated displays. However, the relatively low resolution of the inkjet printing technology limits its further development. In this paper, high-resolution QLEDs were successfully fabricated by electrohydrodynamic (EHD) printing. A pixelated quantum dot (QD) emission layer was formed by printing an insulating Teflon mesh on a spin-coated QD layer. The patterned QLEDs show a high resolution of 2540 pixels per inch (PPI), with a maximum external quantum efficiency (EQE) of 20.29% and brightness of 35816 cd/m. To further demonstrate its potential in full-color display, the fabrication process for the QD layer was changed from spin-coating to EHD printing. The as-printed Teflon effectively blocked direct contact between the hole transport layer and the electron transport layer, thus preventing leakage currents. As a result, the device showed a resolution of 1692 PPI with a maximum EQE of 15.40%. To the best of our knowledge, these results represent the highest resolution and efficiency of pixelated QLEDs using inkjet printing or EHD printing, which demonstrates its huge potential in the application of high-resolution full-color displays.
量子点发光二极管（QLED）因其优异的电致发光特性以及与喷墨打印工艺的兼容性而受到越来越多的关注，这使其在像素化显示器应用中展现出巨大潜力。然而，喷墨打印技术相对较低的分辨率限制了其进一步发展。在本文中，通过电液动力（EHD）打印成功制备了高分辨率的QLED。通过在旋涂的量子点层上打印绝缘的聚四氟乙烯网形成像素化量子点（QD）发射层。图案化的QLED显示出每英寸2540像素（PPI）的高分辨率，最大外量子效率（EQE）为20.29%，亮度为35816 cd/m²。为了进一步证明其在全彩显示中的潜力，将量子点层的制备工艺从旋涂改为EHD打印。打印的聚四氟乙烯有效地阻止了空穴传输层与电子传输层之间的直接接触，从而防止了漏电流。结果，该器件显示出1692 PPI的分辨率，最大EQE为15.40%。据我们所知，这些结果代表了使用喷墨打印或EHD打印的像素化QLED的最高分辨率和效率，这证明了其在高分辨率全彩显示应用中的巨大潜力。
