Аннотация
This paper presents the synthesis of silicon dioxide (SiO₂) from rice husk ash through chemical treatment followed by heat treatment at 800 °C for 3 h. The structural and physicochemical properties of the synthesized silica were investigated using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and laser diffraction particle size analysis. The synthesized silica exhibited an amorphous structure, with a median particle size (D50) of approximately 88.9 μm. Subsequent annealing at 1200 °C led to crystallization of the silica, resulting in the formation of quartz and cristobalite phases. FTIR analysis revealed characteristic absorption bands associated with Si–O–Si stretching vibrations in the 1000–1100 cm⁻¹ region, as well as bands attributed to hydroxyl groups. The obtained crystalline silica materials demonstrate potential for use as powder materials in thermal spraying technologies.