Dataset on accelerated sampling and ageing of atmospheric particulate matter (PM) on bronze coupons for corrosion studies

The present dataset contains data regarding ambient particulate matter (PM) sampled on bronze coupons in the city of Rimini (Italy) between September-October 2020 (summer-autumn campaign) and January-March 2021 (winter-spring campaign). The coupons made of quaternary bronze (Cu-Sn-Zn-Pb) were representative of bronze used for artistic casting in the field of cultural heritage. Specifically, a total of 15 samplings were conducted with different durations and on days with varying meteorological conditions. To evaluate the influence of atmospheric conditions on PM concentration and composition, key hourly parameters were retrieved from the databases of the regional environmental monitoring agency (ARPAE Emilia Romagna). After sampling, coupons with deposited PM were extracted in water and subsequently analysed by ionic chromatography (IC) and total carbon analysis (TC-L) to evaluate ionic concentrations in the soluble fraction. The coupons were then subjected to accelerated ageing in a climatic chamber to reproduce daily and seasonal T, RH and UVA variations. Surface characterisation was performed before and after ageing: Field-emission gun scanning electron microscopy (FEG-SEM) with energy dispersive X-ray spectroscopy (EDS) analyses were performed to investigate the insoluble fraction as well as to monitor any changes in composition after the ageing procedure. Similarly, colour analyses by UV-vis spectrophotometry were performed after PM deposition and after the ageing procedure to measure changes of the surface’s colour. The implemented method of accelerated sampling allowed to collect a sufficient quantity of ambient PM while retaining its compositional complexity. The aim of this study was to investigate PM-induced corrosion of bronze in a controlled environment.