Influence of chemical synthesis process on the properties of calcium hydroxide nanoparticles

Abstract

The objective of the present work was to study the effect of the synthesis process on the properties of Ca(OH)2 nanoparticles (NPs) synthesized using chemical precipitation method. Calcium hydroxide was prepared using Ca(NO3)2·4H2O and NaOH in two different ways. In the first process, the synthesized Ca(OH)2 powder was washed by using DI water to remove nitrate impurity and then dried. In the second process, the synthesized Ca(OH)2 powder was first dried then washed with DI water to remove nitrate impurity and then again dried. The structural, microstructure, surface functional group, thermal and optical properties of the synthesized Ca(OH)2 powders were studied using X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Fourier Transform Infrared (FTIR), Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) and Ultraviolet–Visible (UV–Vis) spectroscopy respectively. A significant change in crystallite size, weight loss and the red shift in the optical bandgap of synthesized Ca(OH)2 nano powder was found with change in synthesis process. These changes are discussed in terms of particles agglomeration behaviour and resulting stress induced during the two different synthesis process.