Synthesis, Textural and Structural Properties of Calcium Hydroxide Nanoparticles in Hydro-Alcoholic Suspension

The use of calcium hydroxide nanoparticles (nanolime) in hydro-alcoholic suspensions represents a good enhancement in particular in the conservation of stones and surfaces of interest in Cultural Heritage. In this work we have produced nanolime by using our alternative method of synthesis (based on the use of a surfactant agent in the original solution) and we have studied, for the first time, structural and morphological properties of the synthesized nanoparticles directly in hydroalcoholic suspension by synchrotron X-ray diffraction technique and transmission electron microscope observations. The particles characterization was performed on suspensions synthesized by varying surfactant content in the synthesis procedure and the water/alcohol ratio, too. We have found that only pure and crystalline Ca(OH)2 particles produced during the synthesis procedure and they maintained stably in suspension. These particles were hexagonally plated and regularly shaped with side dimension ranging from 300 to 40 nm or less; they had a platy habit and they presented, particularly with high alcohol content in suspension, a preferred orientation along z-axis.