POS5-1252
Dibenzofuran-Incorporated Hole Transport Materials Featuring High Bond Dissociation Energy for Efficient and Durable Quantum Dot Light-Emitting Diodes
When and Where
Nov 30, -0001
00:00 - 00:00
Presenter(s)
Youngjun Hwang (Daegu Gyeongbuk Institute of Science and Technology)
Co-Author(s)
Abstract
Quantum dot light-emitting diodes (QLEDs) have attracted significant interest for display and lighting applications because of their precise color tunability, high color purity, and high electroluminescence efficiency. However, their operational stability is often limited by the insufficient electrical robustness of organic hole transport materials (HTMs), particularly owing to their vulnerable phenyl–nitrogen bonds. Herein, a series of dibenzofuran (DBF)-incorporated polymeric HTMs with increased bond dissociation energies (BDEs) were designed and synthesized to simultaneously enhance device efficiency and operational lifetime. Among the synthesized polymers, poly(9,9-dioctylfluorene-co-N,N-diphenyldibenzo[b,d]furan-1-amine) (1-PFDBF) exhibited the most favorable optoelectronic properties, including a high BDE, a deep highest occupied molecular orbital energy level of −5.53 eV, a high hole mobility of 4.40 × 10⁻⁴ cm² V⁻¹ s⁻¹, reduced energetic disorder, suppressed interfacial charge transfer, and a low trap density. Consequently, solution-processed green QLEDs incorporating 1-PFDBF as the hole transport layer achieved a maximum external quantum efficiency of 25.71%, a maximum current efficiency of 102.98 cd A⁻¹, and a maximum power efficiency of 75.69 lm W⁻¹, substantially outperforming conventional poly(9,9-dioctylfluorene-co-N-(4-butylphenyl)diphenylamine)-based devices. Furthermore, the 1-PFDBF-based QLEDs exhibited markedly enhanced operational stability, with extrapolated half-lifetimes of approximately 15,900 h at 1,000 cd m⁻² and 1,456,000 h at 100 cd m⁻².
