Cross-linking strategies for hole transport/emissive layers in quantum-dot light-emitting diodes

Abstract

Due to their excellent features of high efficiency, stability, and high color purity, quantum-dot light-emitting diodes (QD-LEDs) are considered to have great potential as next-generation display technologies. A device should consist of multi-color pixel arrays and corresponding subpixels to fulfill the requirements for high-resolution (HR) QD-LED display panels. Due to the intrinsic solution processability of core-shell structured QDs, the fabrication processes for multi-pixelated HR QD-LED panels are usually transfer printing, inkjet printing (IJP), or photolithography. To avoid the interlayer erosion challenge in the IJP process and direct patterning process of the QD emissive layer (EML), cross-linking strategies have been introduced to construct solvent-resistant films (hole transport layers or QD EMLs) upon exposure to heat or light. This review introduces the recent progress of cross-linking strategies used in hole transport/QD layers of QD-LEDs. Specifically, we present the fundamental chemistries of these cross-linking strategies. We also discuss how these cross-linking methods have been investigated in solution-processed QD-LED devices, especially for IJP/photolithography-based HR QD-LEDs.