Synthesis of Nanosilica from Paddy Husk Ash and Their Surface Functionalization

W.A.P.J Premaratne,S.H.P Gunawardena,A.A.P De Alwis,W.M.G.I Priyadarshana

doi:10.4038/josuk.v8i0.7238

Abstract

Nanosilica was synthesized by a chemical precipitation process from paddy husk ash (PHA) efficiently and effectively. Surface functionalization of the silica nanoparticles was carried out with oleic acid (C18H34O2). Scanning electron micrographs (SEM) data showed that the nanosilica particle size was in the range of 50-70 nm and they were in the agglomerate form. X-ray diffraction (XRD) analysis data revealed that synthesized nanosilica was in amorphous form showing a strong broad peak at 22.14° (2q). Fourier transform infrared spectroscopy (FT-IR) data supported the presence of hydrogen bonded silanol group and siloxane groups in nanosilica. Surface functionalized nanosilica with oleic acid was characterized using thermogravimetric analysis (TGA) and FT-IR methods. FT-IR experimental data showed that the modified nanosilica formed the ester bonding between silanol group in nanosilica and the carboxylic group of oleic acid with a successful functionalization.DOI: http://dx.doi.org/10.4038/josuk.v8i0.7238J. Sci. Univ. Kelaniya 8 (2013): 33-48

Highlights

Nanotechnology has attracted considerable scientific interest due to the new potential uses of particles in 1-100 nanometer scale (Stone et al 2010)
The percentage yield of nanosilica synthesized from burnt paddy husk ash (PHA) at 700 oC was 64%
Fourier transform infrared spectroscopy (FT-IR) data revealed that silica nanoparticles have been successfully functionalized by oleic acid

Summary

INTRODUCTION

Nanotechnology has attracted considerable scientific interest due to the new potential uses of particles in 1-100 nanometer scale (Stone et al 2010). The modification of silica nanoparticles to enhance the surface chemical and physical properties is the key for the successful applications of the material (Guo et al 2008). Nanoscale silica materials are synthesized using several methods, including precipitation from sodium silicate, solgel route, templated synthesis, synthesis using emulsions, and bioinspired methods (Liou et al 2010). It is unclear how these methods are suited for synthesizing nanosilica for a given application by a given silica source. Surface modification of nanosilica particles is carried out with oleic acid to improve the compatibility between inorganic silica nanoparticles and organic matrix for the applications in polymer engineered materials and compounds

MATERIALS AND METHODS

RESULTS AND DISCUSSION

CONCLUSIONS