Synthesis of SiO2-Nanoparticles from Rice Husk Ash and its Comparison with Commercial Amorphous Silica through Material Characterization

Silica is a major inorganic component of rice husk and present in the form of nanoparticle in it. Therefore, it is possible to extract high purity amorphous silica nanoparticles by simple thermo-chemical treatments. So, in this study amorphous silica nanoparticles were tried to produce from rice husk ash through an eco-friendly chemical treatment approach. Characteristics of the extracted nanoparticles were validated by comparing with commercial grade amorphous silica nanoparticles using several material characterization techniques. From X-ray diffraction analysis and Transmission electron microscopy-Selected area electron diffraction patterns, the amorphous behavior was observed for both silica samples, while from Fourier-transform infrared spectroscopy spectra, predominantly siloxane and silanol groups were found. From Scanning Electron, Transmission Electron and Atomic Force Microscopy images, the presence of primary nanoparticles were evidenced along with secondary micro-particles, maybe due to their agglomeration. The diameter of particle was in the range of 17.71 +/- 7.53 nm and 19.49 +/- 13.03 nm for the extracted silica and commercial grade amorphous silica, respectively. Hence, this silica nanoparticles can be utilized in the field of microelectronics, sensors, nano-additives etc.