Electric dipole modulation for boosting carrier recombination in green InP QLEDs under strong electron injection

Abstract

Enhanced and balanced carrier injection is essential to achieve highly efficient green indium phosphide (InP) quantum dot light-emitting diodes (QLEDs). However, due to the poor injection of hole in green...

High-brightness green InP-based QLEDs enabled by in-situ passivating core surface with zinc myristate

“…In addition, with only a slightly larger current density (around 20% larger), the QLED based on ZnMy 2 -treated QDs shows much higher luminance within the entire voltage range, and the peak luminance reaches 175 084 cd m −2 , which is improved by 67% compared to the device without ZnMy 2 (105 127 cd m −2 ). As far as we know, the luminance is the state-of-the-art value among those of the previously reported green InP-based QLEDs [36,37]. Importantly, devices can achieve high brightness even at lower voltages (e.g.…”

Efficient and stable InP quantum-dot light-emitting diodes formed by premixing 2-hydroxyethyl methacrylate into ZnMgO

“…In brief, determining whether to increase or decrease the injection of electrons or holes in the pursuit of efficient QLEDs depends on numerous factors, such as the composition of the materials, the structure of the device, and the device fabrication environment, which leads to various research strategies. 22,[49][50][51] However, research into QLEDs based on InP QDs generally trends towards increasing electron injection because of the shallow conduction band of the InP QDs, 49 making electron injection challenging. Additionally, this finding is consistent with the increased current density observed in QLEDs using H-ZMO compared to those using pristine ZMO, as shown in Fig.…”

Enhanced Performances of Quantum Dot Light-Emitting Diodes with an Organic–Inorganic Hybrid Hole Injection Layer

“…Based on the energy level diagram (Figure 4c), the injection of electrons into the QD emissive layer in QLEDs was slightly easier compared to the injection of holes due to a smaller energy barrier between the ZnO NPs and QDs. The addition of the WOx layer further strengthened the hole injection in the green CdSe@ZnS QLEDs, resulting in a shift of the major recombination center toward the QDs/ZnO interface and a significant enhancement of the recombination rate [33]. The WOx layer effectively acted as an electric dipole layer with electrons diffusing from the PEDOT:PSS and TFB to the deep-lying conduction band of WOx (~6.5 eV) and leaving holes in the PEDOT:PSS and TFB.…”