Rapid sonochemical synthesis of spherical silica nanoparticles derived from brown rice husk

Abstract

The nanoparticles of silica (SiO2) were synthesized from brown rice husk via the sonochemical process, during which the sonication time was varied from 0 to 50 min so as to modulate the material properties of the nano particles. The synthesized SiO2 nanoparticles were confirmed to have amorphous natures in their structural characteristics. The mean particle sizes of the nanoparticles were increased from 5 to 40 nm with increasing sonication time from 0 to 50 min, respectively. The SiO2 nanoparticles synthesized with the sonication time of 50 min showed to possess the highest porosity among our samples. Accordingly, the sample exhibited a higher effective surface area of 271.22 m(2)g(-1). In addition, the bandgap of the SiO2 nanoparticles was decreased from 5.77 to 5.68 eV with increasing sonication time (i.e., 0 -> 50 min). The results suggest that the SiO2 nanoparticles synthesized with an appropriate control of the sonication time (e.g., 50 min) hold promise for future nano ecosystem applications such as nano-biosensors and energy storage nano-devices.