Photocrosslinkers with dual-functional crosslinking mechanisms for direct photolithographic patterning of quantum dots.

Colloidal quantum dots (QDs) hold immense potential for next-generation displays due to their superior color purity and tunable emission, yet their integration into high-resolution devices is hindered by challenges in scalable, low-damage patterning. Conventional methods suffer from solvent-induced degradation, low resolution (>20 μm), and incompatibility with eco-friendly QDs (e.g., InP/ZnS, ZnSe/ZnS). Recent advances in direct optical patterning, including ligand crosslinking and surface engineering, have improved performance but remain limited by reliance on high-energy UV (254 nm), complex ligand synthesis, and poor compatibility with heavy-metal-free QDs. This work introduces ((6-Chloro-1,3,5-triazine-2,4-diyl) bis (oxy)) bis (4,1-phenylene)) bis ((4-(pyrrolidin-1-yl) phenyl) methanone (DBP-T-P), a dual-functional photocrosslinker that crosslinks QD surface ligands and induces surface chlorination, enabling direct photolithographic patterning without complex ligand engineering. DBP-T-P features UV-A compatibility (365 nm), low exposure doses, and simple synthesis, addressing key limitations of prior art. Using DBP-T-P-modified QD inks, we achieved high-quality patterns with 5-μm resolution, preserving >80% photoluminescence quantum yield and reducing surface roughness in both ZnSe/ZnS and InP/ZnS QDs. Air-stable processing and solvent-based development further enhance its scalability. These results establish DBP-T-P as a versatile platform for industrial-scale fabrication of high-resolution, full-color QLEDs and micro-optoelectronic devices.