Photocrosslinking chemistry for direct photopatterning of colloidal nanocrystals: Toward pixelated light emitting diodes and beyond

Abstract

Colloidal quantum dots (QDs) exhibit outstanding optoelectronic properties and solution processability, making them promising candidates for devices such as quantum dot light emitting diodes (QLEDs). The realization of integrated QD‑based devices, particularly in QLED displays, necessitates patterning techniques that offer high resolution, high fidelity, and preserved luminescence. Direct photopatterning via photocrosslinking chemistry has emerged as a promising strategy, which achieves microscale to nanoscale patterning by using light‑triggered reactions of surface ligands to modulate QD colloidal stability without compromising their optical properties. This review outlines recent advances in photocrosslinking‑enabled direct photopatterning of QDs for QLED applications. We begin by introducing the underlying mechanisms and representative photochemistries for direct patterning. Subsequently, we survey various photocrosslinking chemistries and their applications in QD patterning. Drawing on case studies of representative photocrosslinking mechanisms, we discuss key molecular design principles for crosslinkers toward high‑performance QLEDs. Furthermore, we extend the discussion to patterning of other functional nanomaterials, such as metal‑organic frameworks, and to three‑dimensional QD printing. Finally, we conclude with an outlook on future developments and the broadening applications of photocrosslinking‑enabled patterning technologies.