Silicon dioxide hollow microspheres with porous composite structure: Synthesis and characterization

Procedure for preparation of SiO2 hollow microspheres with porous. SEM images show a perfectly whole microsphere and the spherical surface morphology is flowerlike structure. [Display omitted] ► We used template replication method to prepare the hollow porous silica spheres. ► The pore size is changed with the concentration of ammonium hydroxide. ► The surface morphologies are changed with the volume of TEOS. ► Hollow porous silica microspheres with ideally flower structure was obtained. In this paper, a strategy for hollow porous silica microspheres with ideally flower structure is presented. SiO2/PAM hybrid composite microspheres with porous were synthesized by the reaction that the porous polyacrylamide (PAM) micro-gels immersed in tetraethoxysilane (TEOS) anhydrous alcohol solution and water in a moist atmosphere, with ammonium hydroxide as a catalyst. The SiO2 hollow microspheres with porous were obtained after calcination of the composite microspheres at 550°C for 4h. The morphology, composition, and crystalline structure of the microspheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermo-gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FI-IR), and X-ray diffraction (XRD), N2 absorption analysis, respectively. The results indicated that the obtained hollow porous SiO2 microspheres were a perfect flower structure.