Aggregation-Induced Emission Gemini Surfactant-Assisted Fabrication of Shape-Controlled Fluorescent Hollow Mesoporous Silica Nanoparticles

Graphical Shape-controlled hollow aggregation-induced emission (AIE) silica nanoparticles (SNs) and mesoporous silica nanoparticles (MSNs) are prepared. Proper balance of the structure-directing effects of cetyltrimethylammonium bromide (CTAB) and C 16 -tetraphenylethene (TPE)-C 16 allows the morphologies of AIE-SNs and AIE-MSNs to be adjusted from nonfluorescent CTAB-SNs to fluorescent nanostructures. The development of particles that possess different properties has been a long-thought goal for producing multifunctional materials owing to their combination of performance. Herein, aggregation-induced emission (AIE) gemini surfactant-assisted preparation of shape-controlled fluorescent hollow silica nanoparticles (AIE-SNs) is performed directly in water through a one-pot method. The incorporated AIE gemini surfactant (C 16 -TPE-C 16 ) not only provides a fluorophore for the AIE-SNs but also participates in the structure-directing process with cetyltrimethylammonium bromide (CTAB) to regulate their construction. By properly tuning the molar ratio of CTAB and C 16 -TPE-C 16 , AIE-SNs with different morphologies and fluorescence properties can be produced. Their mesoporous silica nanoparticle (AIE-MSN) derivatives can also be fabricated by subsequent extraction owing to the inherent structural differences between CTAB and C 16 -TPE-C 16 . Importantly, fluorescent hollow mesoporous silica nanorods and nanospheres with ordered channels, thin shell thicknesses (~ 13 and ~ 7 nm), high accessible surface areas (599.2 and 573.9 m 2 g –1 ), and uniform pore sizes ~ 2.8 nm) can be facilely prepared at CTAB/C 16 -TPE-C 16 molar ratios of 30:1 and 15:1, respectively. This facile and straightforward method for creating tunable hollow AIE-MSNs may open viable opportunities and inspire the preparation of particles with multiple properties.