Nanoparticles of Sr(OH)2:: synthesis in homogeneous phase at low temperature and application for cultural heritage artefacts

This paper concerns the synthesis and the characterization of nanometer particles of Sr(OH)(2), a moderately high water soluble hydroxide (Ksp= 3.2x10(-4) at 25 degrees C). The reported process yields strontium hydroxide nanoparticles starting from low cost raw materials in aqueous medium (homogeneous phase) at low temperature (below 100 degrees C) by chemical precipitation from salt solutions, involving very simple operational steps and avoiding the use of organic solvents. Observations by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron dispersive X-Ray (EDX) and Fourier transform infrared spectroscopy (FTIR) indicate that the particles are well-crystallized and have nanometer dimensions (similar to 30 nm in diameter). Moreover, experimental evidence shows the potential use of this material for the protection and the consolidation of wall paintings (frescoes), paper, stone, wood and other artistic artefacts.