New nanomaterials for protecting and consolidating stone
In general, the synthesis of nanocomposites to obtain a final homogenous dispersion is a tricky step, depending on the type of: chosen preparation method, solvent, and particles concentrations.
In our case, several preliminary laboratory tests were carried out to obtain a homogenous dispersion, without formation of protruded aggregates. SEM images of statuary Carrara marble treated with Rhodorsil RC80 and 0.2% (a), 1% (b), 2% (c) w/v silica nanoparticles To simulate a treatment, as it happens in a real situation, the obtained suspensions were applied on the surface of the stones by brushing until visible refusal and repeating the treatment after 4 hours .
In fact all cultural heritage undergoes aging processes with final degradation effects, due to their intrinsic material properties and deterioration phenomena, which are influenced by environmental conditions such as climate, pollution, biological agents, and mechanical stresses.Only few regulations exist and for artificial solar irradiation, the NORMA UNI 10925-2011 –which concerns the methodology for artificial solar light test applied on natural and artificial stones– was applied.Following this standard method, a climatic chamber (SOLARBOX 1550 E) equipped with a xenon arc light source, 1500 W, with spectral range from 280 to 800 nm, was used and samples underwent constant irradiation at 1000W/m, the specific irradiation conditions required by the above standard norm.In the Unit, advanced diagnostic expertise and instrumentation [Scanning Electronic Microscopy (SEM), Transmission Electronic Microscopy (TEM), Optical Microscopy (OM), X Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), X Ray Fluorescence (XRF), Ultrasound (US), Termogravimetry (TG), Differential Thermal Analyses (TDA), Raman spectroscopy, light scattering and N adsorption at 77K to explore nanomaterials surface characteristics, zeta potential to measure nanofluid stability.All these characterization skills and capabilities are conjugated with nanopowder synthesis capabilities in this study.