These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Small Molecule-Modified Hole Transport Layer Targeting Low Turn-On-Voltage, Bright, and Efficient Full-Color Quantum Dot Light Emitting Diodes.
    Author: Li J, Liang Z, Su Q, Jin H, Wang K, Xu G, Xu X.
    Journal: ACS Appl Mater Interfaces; 2018 Jan 31; 10(4):3865-3873. PubMed ID: 29302957.
    Abstract:
    For an organic-inorganic hybrid quantum dot light-emitting diode (QD-LED), enhancing hole injection into the emitter for charge balance is a priority to achieve efficient device performance. Aiming at this, we employ N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)benzidine (TPD) as the additional hole transport material which was mixed with poly(9-vinylcarbazole) (PVK) to form a composite hole transport layer (HTL) or was employed to construct a TPD/PVK bilayer structure. Enabled by this TPD modification, the green QD-LED (at a wavelength of 515 nm) exhibits a subband gap turn-on voltage of 2.3 V and a highest luminance up to 56 157 cd/m2. Meanwhile, such TPD modification is also beneficial to acquire efficient blue and red QD-LEDs. In particular, the external quantum efficiencies (EQEs) for these optimized full-color QD-LEDs are 8.62, 9.22, and 13.40%, which are 3-4 times higher than those of their pure PVK-based counterparts. Revealed by the electrochemical impedance spectroscopy, the improved electroluminescent efficiency is ascribable to the reductions of recombination resistance and charge-transfer resistance. The prepared QD-LEDs surpass the EQE values achieved in previous reports, considering devices with small-molecule-modified HTLs. This work offers a general but simple and very effective approach to realize the low turn-on-voltage, bright, and efficient full-color QD-LEDs via this solution-processable HTL modification.
    [Abstract] [Full Text] [Related] [New Search]