XXVI Congresso Nazionale della Società Chimica Italiana- 11 Settembre 2017, Paestum (SA)

Within a current National Smart Cities (SCN_00520) project, entitled ‘Product and process innovation for maintenance, preservation and sustainable programmed restoration of Cultural Heritage’1, the use of XPS (X-ray Photoelectron Spectroscopy) as a surface-specific technique, in combination with complementary surface and analytical techniques, is aimed at contributing to the diagnostic phase of the project whose procedural accuracy is essential to set intervention priorities. Since deterioration of any kind, due to ageing, natural or anthropogenic factors, begins from surface reactions, XPS can be suitably employed for the ex-situ compositional characterization of degraded compounds properly scraped from surfaces. The present contribution is focussed on the study of the main degradation products forming on stones constituting artifacts/monumental buildings in the areas of cultural heritage belonging to the municipalities of the Basilicata region. In particular, it was intended to complete the surface characterization provided by combined surface techniques2 of a reference sample, properly sized (about 1m3 ), using Gravina calcarenite stones, and placed in a site with reported coordinates in the industrial area of S. Nicola di Melfi. In the previous work, the effect of local environments on its North, South, East and West surfaces was evaluated after three and six months of exposition, revealing already incipient degradation also influenced by the exposition side2 . Here, we show the elaboration of additional XPS data acquired over an extended period, using the same curve-fitting procedure3, as before. The whole data set will then be statistically interpreted for attempting a better rationalization of the alteration phenomena due to concomitant ageing, natural or anthropogenic factors occurring in real situations