Design and synthesis of multi-functional silsesquioxane nanoparticles having two distinct optoelectronic functionalities

Abstract

Multi-functional silsesquioxane nanoparticles (SQ-NPs) having two distinct optoelectronic functionalities on a single arm were prepared using a thiol-epoxy click reaction followed by esterification. The epoxy-functionalized SQ-NPs were prepared from commercially available (3-glycidyloxypropyl)triethoxysilane and were employed in the thiol-epoxy click reaction to introduce aromatic and heterocyclic thiol compounds, such as naphthalenethiol, 2-mercapto-1-methylimidazole, and 4,5-diphenyl-2-oxazolethiol. The resulting hydroxyl-functionalized SQ-NPs were further functionalized via esterification to incorporate a second functional group. The X-ray diffraction (XRD), size-exclusion chromatography (SEC), and scanning force microscopy (SFM) results indicated the formation of SQ-NPs ( 300 °C), and characteristic optoelectronic properties with a wide range of Stokes shifts (5200–12,000 cm−1). The optoelectronic properties of the multi-functional SQ-NPs could be controlled by modifying the structure of the two distinct functional groups, which could be easily tuned by varying the structure of the thiol compounds and acid chloride derivatives in the feed.