Recent Advances in Bio-Derived Nanomaterials: Green Synthesis of Silica

Abstract

Silica molecules present in commercial objects can pose a hazard to human health, which is why the environmentally friendly synthesis of silica has been intensively researched in the recent decades. This chapter describes the synthesis of silica from sugarcane bagasse waste and its physical and chemical properties for potential use in eco-friendly applications. Sugarcane bagasse was burned to produce ash, which was then calcined in a 700°C kiln before being treated with citric acid to remove silica from the ash. X-ray fluorescence (XRF) analysis showed that after the acid treatment, 78–79% of the silica was produced and strong peaks were observed in the X-ray diffraction spectra (XRD) at 2Ɵ = 28 (degree) and an average diameter of 28 nm for 1-HDTA and 30 nm for TPAH, determined by the Scherrer equation. Fourier transform infrared spectroscopy (FTIR) spectra also confirms the presence of synthesized silica. In addition, the shape of the particles was analyzed by TEM and SEM images and it is found that synthesized silica had a spongy shape with irregular sizes ranging from 25 to 50 nm. Overall, the studies show that organic bases are capable of synthesizing silica with application-specific properties from agricultural waste using green chemistry.