Synthesis and Characterization of Hollow Silica Microspheres

CaCO₃/SiO₂ core-shell structure was prepared by sol-gel route and using calcium carbonate microparticles as core templates and TEOS as silica source,and then the hollow silica microspheres were synthesized after calcination,dissolution and washing process.The surface morphology,structure and compressive strength of hollow silica microspheres were examined and determined by using SEM,XRD,FTIR,TG and compression tester.The results show that the as-synthesized hollow silica microspheres are uniform spherical particles with good dispersion,and have a diameter of 2~5 μm,wall thickness of 0.42~0.85 μm,specific surface area of 554.01 m²/g,pore diameter around 1.7 nm and compressive strength of 20~30 MPa.