TS Science

There has been considerable progress in colloidal quantum dot light-emitting diodes (QD-LEDs) for display applications. However, their commercialization remains challenging, because of the difficulty in achieving high-resolution, full-color patterning of quantum dots (QDs) without degrading their optical properties. Direct photolithography has attracted attention, but it often requires complicated ligand-exchange processes and causes ultraviolet (UV)-induced QD degradation. Herein, a nondestructive, universal QD patterning method that blends QDs with a photocrosslinkable hole-transport layer (HTL) polymer, poly(9-vinylcarbazole), is presented. Upon UV irradiation, the resulting blended films form a robust crosslinked network that encapsulates and protects the QDs, enabling high-resolution patterning while preserving their optical properties. By employing this strategy to cadmium (Cd)-based QDs, monochrome resolutions exceeding 10 000 pixels per inch are achieved, without requiring ligand-exchange steps. Furthermore, incorporating this photocrosslinked blended emissive layer into QD-LEDs enhances the device performance by suppressing excess electron injection and improving hole injection, leading to a 1.7 fold increase in the external quantum efficiency and a three fold extension of operational lifetimes. Notably, this process can be readily applied to diverse QDs, including Cd-free variants and other functional nanocrystals, highlighting the broad applicability and commercial potential of this photocrosslinkable QD-HTL platform for next-generation display technologies.