Fabrication and study of superficially porous core-shell SiO2@SiO2 microspheres

ABSTRCTCore-shell structure particles are attracting considerable attention because of their applications in drug delivery and catalysis carrier. In this study, SiO2@SiO2 core-shell structure with tunable shell thickness was successfully prepared by using tetraethoxysilane (TEOS) as the silica source. Monodisperse nonporous silica spheres with a diameter of 1.7 μm were synthesized by a modified Stöber method. An template CTAB was first grafted onto the SiO2 microsphere surface. Then TEOS was hydrolyzed with the addition of ammonia. Finally, superficially porous core-shell SiO2@SiO2 microspheres were obtained through calcination to remove the template.