Dibenzofuran-based Cross-linkable Hole Transport Materials for Highly Efficient Solution-processed Quantum Dot Light Emitting Diodes

Abstract

Cross-linkable hole transport materials (HTMs) are a feasible strategy for solutionprocessed quantum dot light-emitting diodes (QLEDs). However, previously developed cross-linkable HTMs showed poor hole transport properties, high cross-linking temperatures, which are all major obstacles to achieving high performance in solution-processed QLEDs. To address these issues, we designed and synthesized cross-linkable HTMs based on triphenylamine (TPA) with divinyl functional groups at the various positions of dibenzofuran (DBF). Notably, cross-linked 4-(dibenzo [b,d]furan-3-yl)-N,N-bis(4-vinylphenyl)aniline (3-CDTPA) exhibited a deep highest occupied molecular orbital energy level (5.50 eV), high hole mobility (2.44×104 cm2 V 1 s 1), low cross-linking temperature (150 ℃) as well as high external quantum efficiency, maximum current efficiency, and maximum power efficiency of 18.59%, 78.48 cdA1 , and 78.14 lmW1 , respectively.