Articolo in rivista, 2020, ENG, 10.3390/proceedings2020062011

Functional Nano-Hydroxyapatite for Applications in Conservation of Stony Monuments of Cultural Heritage

Capitelli Francesco 1; Dida Bujar 2; Della Ventura Giancarlo 3; Baldassarre Francesco 4; Capelli Davide 1; Senesi Giorgio S. 5; Mele Altin 6; Siliqi Dritan 4

1) Istituto di Cristallografia, IC-CNR, Via Salaria Km 29.300, 00016 Rome, Italy; 2) FIMIF, University Polytechnic of Tirana, 1001 Tirana, Albania; 3) Dipartimento di Scienze, Università Roma Tre, Largo S. L. Murialdo 1, 00146 Rome, Italy; 4) Istituto di Cristallografia, IC-CNR, Via G. Amendola, 122/O, 70126 Bari, Italy; 5) Istituto per la Scienza e Tecnologia dei Plasmi, ISTP-CNR, Via G. Amendola, 122/O, 70126 Bari, Italy; 6) Ivodent Academy, Center of Techniques Studies, 1010 Tirana, Albania.

Stony monuments must continuously be safeguarded from damage caused over time, in particular from the detrimental effects of weathering. One of the new environmentally-friendly (nano) materials for stone reinforcement, particularly suitable for marble and calcareous (limestone, sandstone) artifacts, is Ca10(PO4)6(OH)2 hydroxyapatite (HAp), which has a considerably lower dissolution rate and solubility compared to CaCO3 calcite (the building block of marble materials): thus, HAp has been proposed for the protection of calcareous monuments against acidic rain corrosion. Promising results have been obtained, but further optimization is necessary as the treated layer is often incomplete, cracked and/or porous. Several parameters need to be optimized, in this way a homogeneous layer can be obtained, and consequently the formation of metastable can be avoided, soluble phases instead of HAp. These include: the pH of the starting solution; the effect of organic and inorganic additions in particular, that of ethanol, which is known to adsorb calcite, thus possibly favoring the growth of the HAp layer. The formation of HAp nanoparticles and their application on stony substrates has been investigated by means of a multi-methodological approach based on scanning electron microscopy, x-ray diffraction, small- and/or wide-angle x-ray scattering, Fourier-transform infrared spectroscopy, and finally, in situ measurements of laser-induced breakdown spectroscopy and acid attack preliminary tests on stony substrates.

Proceedings (MDPI) 62 (11), pp. 1–10

Keywords

hydroxyapatite, nanoparticles, synthesis, structural characterization, stony monuments, laser-induced breakdown spectroscopy

CNR authors

Capitelli Francesco, Senesi Giorgio Saverio, Siliqi Dritan, Baldassarre Francesco, Capelli Davide

CNR institutes

IC – Istituto di cristallografia, ISTP – Istituto per la Scienza e Tecnologia dei Plasmi

ID: 446459

Year: 2020

Type: Articolo in rivista

Creation: 2021-02-27 21:02:00.000

Last update: 2022-12-07 10:22:45.000

External IDs

CNR OAI-PMH: oai:it.cnr:prodotti:446459

DOI: 10.3390/proceedings2020062011