The effect of fluorine ion on fabrication of nanostructure forsterite during mechanochemical synthesis

摘要

Pure nanocrystalline forsterite could be fabricated by mechanochemical synthesis in the presence of fluorine ion. Mechanochemical process and post-heat treatment were performed using MgCO_3, SiO_2 and (NH_4)SiF_6 powders as starting materials. Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques were utilized to characterize the synthesized powders. Pure forsterite could be obtained after 5 h of mechanical activation and post-heat treatment for 1 h at 900 deg C. Nanocrystalline forsterite was fabricated with the grain size of about 30 nm. The synthesized forsterite nanopowder had particle size smaller than 100 nm. The results showed that in the presence of fluorine ion, the rate of forsterite formation was increased by combustion reaction.