Photoclick Thiol‐Ene Reaction as a Tool to Control Linking Between Gold Particles and Silica Surfaces

Abstract The control over the positioning of optically active nanoparticles (NPs) on other materials can be crucial for designing multicomponent devices with defined optical properties. In this work, a selective anchoring method based on the photochemical radical thiol‐ene addition (PRTEA) click chemistry reaction is presented. Spherical and star‐shaped gold nanoparticles (AuNPs) are attached to the surface of SBA‐15 mesoporous silica, under irradiation in presence of a photoinitiator. To this end, both SBA‐15 and AuNPs are appropriately functionalized using sol‐gel chemistry and ligand exchange, respectively, with the groups involved in PRTEA reaction (thiol and vinyl). In a first step, the feasibility of selectively binding AuNPs to SBA‐15 is demonstrated, resulting in colored powders. Additionally, the selective covalent anchoring of one type of nanoparticles over another is demonstrated. When the reaction is performed in the presence of a mixture of AuNPs with and without the thiol moieties, it is observed that only those properly functionalized for PRTEA are bound to vinyl‐functionalized SBA‐15. Overall, the results presented here demonstrate that PRTEA reaction is an excellent alternative for the selective binding of NPs with distinct optical properties to materials, facilitating the development of a diverse range of optically active materials.