Synthesis and characterization of nanosilica prepared by precipitation method

Nanosilica was prepared by precipitation method and was characterized by various analytical tools. From transmission electron micrograph the silica particles are found to have almost spherical shape with a dimension of similar to50 nm. The surface area is found to be of 560 m(2) g(-1) and density 2.2 g cm(-3). From thermogravimetric analysis the total silanol density in the silica is found to be 7.68 nm(-2). A two tier hydration model is proposed from the results of thermogravimetric analysis. The number of reactive silanols that forms hydrogen bond with water molecules is found to be 2.48. The infrared spectral data supports the presence of hydrogen bonded silanol group and the siloxane groups in silica. (C) 2004 Elsevier B.V. All rights reserved.