Maheshwaran Athithan, Bae Hyejeong, Park Jaehyoung, Jung Hyeonwoo, Hwang Youngjun, Kim Jongyoun, Park Chaehyun, Kang Byeongjae, Song Myungkwan, Lee Youngu
Department of Energy Science & Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333, Techno Jungang Daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea.
Department of Energy & Electronic Materials, Korea Institute of Materials Science (KIMS), 797 Changwon-daero, Sungsan-gu, Changwon-si, Gyeongsangnam-do 51508, Republic of Korea.
ACS Appl Mater Interfaces. 2023 Sep 27;15(38):45167-45176. doi: 10.1021/acsami.3c09106. Epub 2023 Sep 12.
Cross-linkable hole transport materials (HTMs) are ideal for improving the performance of solution-processed quantum dot light-emitting diodes (QLEDs) and phosphorescent light-emitting diodes (OLEDs). However, previously developed cross-linkable HTMs possessed poor hole transport properties, high cross-linking temperatures, and long curing times. To achieve efficient cross-linkable HTMs with high mobility, low cross-linking temperature, and short curing time, we designed and synthesized a series of low-temperature cross-linkable HTMs comprising dibenzofuran (DBF) and 4-divinyltriphenylamine (TPA) segments for highly efficient solution-processed QLEDs and OLEDs. The introduction of divinyl-functionalized TPA in various positions of the DBF core remarkably affected their chemical, physical, and electrochemical properties. In particular, cross-linked 4-(dibenzo[,]furan-3-yl)-,-bis(4-vinylphenyl)aniline (3-CDTPA) exhibited a deep highest occupied molecular orbital energy level (5.50 eV), high hole mobility (2.44 × 10 cm V s), low cross-linking temperature (150 °C), and short curing time (30 min). Furthermore, a green QLED with 3-CDTPA as the hole transport layer (HTL) exhibited a notable maximum external quantum efficiency (EQE) of 18.59% with a remarkable maximum current efficiency (CE) of 78.48 cd A. In addition, solution-processed green OLEDs with 3-CDTPA showed excellent device performance with an EQE of 15.61%, a CE of 52.51 cd A, and outstanding CIE(, ) color coordinates of (0.29, 0.61). This is one of the highest reported EQEs and CEs with high color purity for green solution-processed QLEDs and OLEDs using a divinyl-functionalized cross-linked HTM as the HTL. We believe that this study provides a new strategy for designing and synthesizing practical cross-linakable HTMs with enhanced performance for highly efficient solution-processed QLEDs and OLEDs.
可交联空穴传输材料（HTMs）对于提高溶液法制备的量子点发光二极管（QLEDs）和磷光发光二极管（OLEDs）的性能而言是理想的。然而，先前开发的可交联HTMs具有较差的空穴传输性能、较高的交联温度和较长的固化时间。为了实现具有高迁移率、低交联温度和短固化时间的高效可交联HTMs，我们设计并合成了一系列包含二苯并呋喃（DBF）和4-二乙烯基三苯胺（TPA）片段的低温可交联HTMs，用于高效溶液法制备的QLEDs和OLEDs。在DBF核的不同位置引入二乙烯基官能化的TPA显著影响了它们的化学、物理和电化学性质。特别地，交联后的4-(二苯并[，]呋喃-3-基)-，-双(4-乙烯基苯基)苯胺（3-CDTPA）表现出较深的最高占据分子轨道能级（5.50 eV）、较高的空穴迁移率（2.44×10 cm V s）、较低的交联温度（150°C）和较短的固化时间（30分钟）。此外，以3-CDTPA作为空穴传输层（HTL）的绿色QLED表现出显著的最大外量子效率（EQE）为18.59%，以及显著的最大电流效率（CE）为78.48 cd A。此外，采用3-CDTPA的溶液法制备的绿色OLED表现出优异的器件性能，EQE为15.61%，CE为52.51 cd A，以及出色的CIE(，)色坐标为(0.29, 0.61)。这是使用二乙烯基官能化交联HTM作为HTL的绿色溶液法制备的QLEDs和OLEDs中报道的最高EQEs和CEs之一，且具有高色纯度。我们相信这项研究为设计和合成具有增强性能的实用可交联HTMs提供了一种新策略，用于高效溶液法制备的QLEDs和OLEDs。
