Olefin Ligand Metathesis for Colloidal Emissive Nanocrystals with Enhanced Stability and Photosensitivity

High-resolution patterning of colloidal perovskite nanocrystals (PNCs) is essential for next-generation display technologies, yet conventional approaches relying on exogenous photosensitive ligands or additives often compromise optical properties and colloidal stability. Here, we present a nondestructive ligand modification strategy based on olefin metathesis, in which original oleic acid and oleylamine ligands are converted into metathesized ligands featuring dual anchoring groups and shortened chains. This structural transformation enhances colloidal stability through stronger chelation and reduced conformational entropy of possible ligand configurations. The removal of sterically hindering hydrocarbon chains exposes reactive alkene moieties, enhancing the photosensitivity of PNCs. The resulting metathesized PNCs (PNC-M) exhibit excellent photoluminescence quantum yield (PLQY) retention (>93% after 3 weeks) and strong resistance to structural degradation under ambient conditions. Molecular dynamics simulations confirm the strengthened surface-ligand interactions in PNC-M, consistent with the experimentally observed structural robustness. Furthermore, PNC-M enables efficient direct optical lithography at substantially reduced UV doses via alkene polymerization and hydrothiolation, clearly outperforming pristine PNCs (PNC-P). This strategy offers a general, nondestructive ligand engineering method for various emissive nanocrystals, including II-VI and III-V quantum dots, and facilitates high-resolution lithography under reduced UV exposure by leveraging the enhanced photosensitivity imparted by olefin ligand metathesis.