Versatile dendrimer-derived nanocrystal microreactors towards fluorescence colloidal photonic crystals

Abstract

The ability to finely bind colloidal photonic crystals with nanocrystals (NCs) is critical in many applications ranging from light-emitting devices to flexible displays and biological labels. Herein, the use of carbosilane–thioether generation 2 vinyl-terminated (G2-Vi) dendrimers facilitates zero dimensional (0D) and two dimensional (2D) microreactors with high-uptake NCs, allowing them to generate fluorescent colloidal photonic crystals. Dendrimer-functionalized microspheres were prepared by seeded copolymerization from micrometer-sized polystyrene (PS) seed particles and G2-Vi dendrimers. As an independent 0D microreactor, such dendrimer-functionalized microsphere latices bearing abundant thioether anchor sites can capture guest metal ion components, followed by the introduction of chalcogenides, and hence the in situ generation of higher-uptake NCs was realized. Furthermore, the as-obtained NC–latex hybrids from 0D microreactors were directly self-assembled into large-scale ordered colloidal arrays with uniform fluorescence. Additionally, compact assemblies from the Cd²⁺-loaded dendrimer-functionalized microspheres were constructed and were employed as a large-scale 2D reactor. An on-demand fluorescence pattern was freely and quickly displayed via a reaction-induce-response process by screen stencil oriented printing.