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[Display omitted] • T5DP36 with one-dimensional transport channel deserved super carrier mobility. • One-dimensional transport channel was firstly constructed in CHTL (T5DP36:V-CBP). • One-dimensional transport channels in CHTL are formed by π-π interaction of T5DP36. • The carrier mobility of CHTL was boosted from 6.6 × 10−5 to 2.16 × 10−3 cm2V−1s−1. • The EQE of blue QLED has increased from 10.03% to 18.16%, which is the cutting edge. Quantum dot light-emitting diodes (QLEDs) emerged as very competitive candidates for next generation display and lighting applications. Cross-linked hole transport materials (HTMs) permit the flourish of solution-processed QLEDs. Whereas, unbalanced charge injection and energy level mismatch happened to cross-linked HTMs severely suppress the efficiency of blue QLEDs, which limits the full-color display application. Here, discoid molecules with self-assembly behavior were firstly proposed to construct one-dimensional transport channels in cross-linked hole transport layer (HTL) to advance the carrier transport property of the target composite HTL (CHTL). Compared with CHTLs prepared from amorphous and disordered crystalline discoid molecules, the carrier mobility of CHTL (T5DP36: V-CBP) with one-dimensional transport channels was signally boosted by two orders of magnitude from 6.6 × 10−5 to 2.16 × 10−3 cm2 V−1 s−1. The relevant blue QLED was qualified with notably enhanced external quantum efficiency of 18.16 %, deep blue emission with Commission International de I'Eclaiiage of (0.14, 0.04) and extended T 50 lifetime from 177 to 417 h under 100 cd m−2. This is at a cutting edge of deep blue light and eligible for high-end display applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Indium tin oxide was hybrid modified with MoO 3 and self-assembled monolayer. • Self-assembled monolayer was used to adjust oxygen vacancies in MoO 3. • Solution-processed hole transport layer-free OLED achieved EQE max of 18.18% Compared with current vacuum-deposited multilayer organic light-emitting diodes (OLEDs), solution-processed simplified-structured OLEDs are more appealing by merits of low costs and promising potentials in large-area OLEDs. Nevertheless, it remains challenging due to intermixing between adjacent organic layers. Herein, indium tin oxide (ITO) surface was deposited with molybdenum trioxide (MoO 3) and then modified with self-assembled monolayer (SAM) of pentafluorobenzyl phosphonic acid. The SAM modification process made the MoO x film rich in oxygen vacancies, which ensured effective hole injection from the hybrid modified ITO directly to the emitting layer. This strategy facilitates HTL-free OLEDs and then completely avoids interlayer intermixing. Using the hybrid modified ITO as anode, HTL-free solution-processed green phosphorescent OLED was prepared and achieved a maximum current efficiency of 63.24 cd A−1 and a maximum external quantum efficiency of 18.18%. Meanwhile, preferable operational stability than standard multilayer OLEDs was obtained. For red phosphorescent OLED, a maximum external quantum efficiency of 17.49% was achieved. This work proposed a new way of adjusting cation valence to improve hole injection, contributing to solution-processed OLED fabrication. [ABSTRACT FROM AUTHOR]

• QD films based on modified Poly-TPD exhibited higher PL intensity and lower fluorescence quenching properties. • Reduced defects density at the interface between QD films and Poly-TPD modified with diamine molecules. • QLEDs exhibited a distinctly enhancement in EQE from 4.93 to 8.90%. Inorganic perovskite quantum dots (QDs) have emerged as promising materials for light-emitting devices by merits of their high photoluminescence quantum yield (PLQY), narrow full width at half-maximum and tunable emission spectrum. However, fluorescence quenching and trap-mediated nonradiative recombination between hole transport layer (HTL) and QD films are prejudicial to the performance of perovskite-QDs-based light-emitting devices (QLEDs). Here, HTL was modified with diamine molecules (1,4-butanediamine (4-DA), 1,8-octyldiamine (8-DA) and 1,11-aminoundecylamine (11-DA)) through a simple self-assembly method. QD films based on modified poly[ N , N ′-bis(4-butylphenyl)- N , N ′-bis(phenyl)-benzidine] (Poly-TPD) exhibited higher PL intensity and lower fluorescence quenching properties. Meanwhile, diamine molecules do favor to the flatness of Poly-TPD film and contribute to the smoothness of QD films. Moreover, the exciton quenching and the density of defects at the interface between HTL and QD films were effectively reduced. Particularly, QLEDs based on HTL modified with 8-DA was endowed with a maximum luminance of 78634 cd/m2, a peak current efficiency of 30.77 cd/A, a maximum external quantum efficiency of 8.90% and T 50 of 16.8 min when the initial brightness is about 1000 cd/m2. [ABSTRACT FROM AUTHOR]

• Two vinyl-based cross-linkable hole transporting materials are synthesized. • Cross-linking temperature is markedly lowered by doping photoinitiator. • Hole mobility is also enhanced by doping photoinitiator. • The highest external quantum efficiencies are 15.5% (green) and 15.0% (red). Recently, developing insoluble cross-linkable functional layers plays a vital role for solution-processed organic light emitting diodes (OLEDs). Here, two vinyl-based cross-linkable hole transporting materials V-TPAVTPD and V-TPAVCBP are designed and synthesized. Additionally, cationic photoinitiator 4-octyloxydiphenyliodonium hexafluoroantimonate (OPPI) is first introduced to chemically induce vinyl-based photo cross-linking process, aiming at lowering cross-linking temperature and enhancing hole mobility. As a result, cross-linking can occur at expressly low temperature of 120 °C with >95% solvent resistance. Moreover, hole mobility is markedly enhanced with the value higher than 10−3 cm2 V−1 s−1. When applying hole transporting layers (HTLs) to solution-processed green and red phosphorescent OLEDs, devices exhibit excellent properties. Particularly, the maximum current efficiency of 54.0 cd A−1 (green), 9.8 cd A−1 (red) and external quantum efficiency of 15.5% (green), 15.0% (red) are obtained when OPPI doped V-TPAVCBP serves as HTL. This low temperature feasible cross-linking process to prepare HTLs with preferable hole mobility promotes the development of OLEDs. [ABSTRACT FROM AUTHOR]