A facile “polystyrene-dissolving” strategy to hollow periodic mesoporous organosilica with flexible structure-tailorability

Abstract A facile “template dissolving” strategy has been developed for the fabrication of hollow periodic mesoporous organosilica (HPMO) particles with perpendicularly ordered mesopores, where polystyrene (PS) is used as sacrifice template for the generation of hollow cavity. Systematic characterizations including transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and N 2 adsorption/desorption analysis clearly reveal that the HPMO particles have an excellent monodispersity with a high specific surface area of 1246.7 m 2  g −1 , large pore volume of 1.38 cm 3  g −1 and uniformly ordered mesopores of 2.48 nm. The pre-encapsulation of a core into PS (SiO 2 , Fe 3 O 4 @SiO 2 ) results in a yolk-shell (Y-S) particle with high tunable shell thickness (30–60 nm) and cavity size (230–450 nm). The magnetically recyclable Fe 3 O 4 -YS-PMO was further utilized to adsorb 2, 4-dichlorophenol (2, 4-DCP) and the controlled release of camptothecin (CPT). Up to 81 mg of CPT was loaded per gram of the Fe 3 O 4 -YS-PMO particles, followed with a continuously release of 76% within 5 days.