Preparation and Phase Evolution of Wollastonite by Sol-Gel Combustion Method Using Sucrose as the Fuel

Abstract

Wollastonite is a bioactive material (molecular formula of CaSiO₃) that belongs to the class of calcium silicate. It is widely used as a bone regenerative material and as a drug delivery carrier due to its high bioactivity and biocompatibility. A novel sol-gel combustion synthesis has been adopted by using sucrose as a fuel and nitric acid as an oxidizer to synthesize wollastonite. Calcium nitrate and tetraethyl orthosilicate were taken as the source of calcium and silicate. The obtained powders were characterized by powder X-ray diffraction to check the phase formation and Fourier transform infrared (FT-IR) spectroscopy for the identification of the characteristic functional group. The average particle size calculated by using Scherer's formula is 51.7 nm, and the lattice parameter values are found to be a = 15.4301 Å, b = 7.3242 Å, and c = 7.017 Å. The phase transformation studies were carried out by using a thermogravimetric analyzer. The morphology of the pure wollastonite was imaged by using scanning electron microscopy and atomic force microscopy; the images shows irregular spheroid-shaped particles.

Keywords:

• Atomic force microscopy
• Phase evolution
• Scanning electron microscopy
• Sol-gel combustion
• Wollastonite

ACKNOWLEDGMENTS

The authors thank VIT University for the financial support and Prof. R. Vijayaraghavan, Assistant Director, Center for Excellence in Nanomaterials, VIT University, for providing the facilities to carry out some of the experimental work.