Synthesis of silica nanoparticles from rice husk ash

Silica nanoparticles (SiO2 NPs) were synthesized from rice husk ash (RHA) by chemical treatment and calcination. The size of SiO2 NPs evaluated by transmission electron microscope (TEM) was of 20 - 50 nm and the size distribution of SiO2 NPs measured by dynamic laser scattering (DLS) was of Gaussian mode. The X-ray diffraction (XRD) pattern with only one peak at 2θ ~ 220 confirmed the amorphous phase of SiO2 NPs. The Fourier transform infrared (FTIR) and energydispersive X-ray (EDX) spectra were also used to evaluate the functional groups and the purity of SiO2 NPs. The SiO2 NPs powder with high purity could be suitably produced by calcination of acid treated RHA at 7000C for 2h. The obtained SiO2 NPs product can be potentially used for numerous purposes of application, especially as filler in paints.