Aim and Background: Todays, the demand and application areas of nanoparticles, especially silica nanoparticles have been increased, progressively. Hence, there is always an effort to find new sources for producing nanoparticles with minimal cost and environmental problems. In this study, the horsetail plant which is categorized in the group of plants with high silica content has been used to synthesis silica nanoparticles.

Materials and Methods: To do this, the ash obtained from this plant after the calcination process and several steps of acid leaching was characterized by different methods. The morphology, chemical composition, and crystal structure of the synthesized silica nanoparticles were investigated by the scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray fluorescence (XRF) methods, respectively. Also, the specific surface area of the particles was determined by the BET technique.

Results: The results showed that the synthesized silica powder had a high purity (97.5 %), amorphous structure, an average particle size of about 30 nm, and a porous structure with surface area of about 410 m2/g, and pore diameter of 11.6 nm.

Conclusion: Therefore, the ash obtained from the horsetail plant can be used to produce porous silica nanoparticles with appropriate functional properties.