Dual Cluster-Surface Click Chemistries on Silver Nanoclusters

Nanoclusters'(NCs) unique chemical and photophysical properties make them among the most studied nanomaterials for applications in biosensing, catalysis, and emissive materials. Toward these, there is a need to develop NCs with ligands tuned for the desired application. This can be accomplished through direct synthesis of individual NCs or through postsynthetic reactions. Cluster surface (CS) click chemistry provides an advantageous route to produce a library of NCS from a single reactive NCs while not changing the cluster core, although examples of this are still scarce, considering the vast library of NCs. Here, the synthesis and characterization of two new azide-functionalized Ag₂₀ NCs with a carbonate template and demonstration of their cluster-surface Staudinger-Bertozzi ligation (CS-SBL) reactivity are reported. Furthermore, a dual-surface double-click strategy using CS-SBL followed by cluster-surface strain-promoted azide-alkyne cycloadditions is showcased as a promising method to introduce multiple complementary functionalities under kinetic control.