Preparation of spherical microfine silicon powder

Abstract

Under certain conditions of proper temperature and pH value, sodium silicate was hydrolyzed in liquid ammonia chloride, and spherical microfine SiO₂ powder in micrometer-size was prepared. In this experiment, the relationship between needed time and proper pH value, temperature, density of the solution, and its current capacity were found. The optimum conditions are pH 8.5, 70 °C, and the concentration of sodium silicate is 0.6 mol/L for the density of the solution. The structure of spherical microfine silicon was charactetized by SEM and XRD.

Keywords

SiO₂ / powder / spherical-structure

References

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