Application of X-ray Photoelectron Spectroscopy (XPS) to chemical surface analysis of Particulate Matter (PM) is not yet a routine method in aerosol characterisation. Nonetheless, in the last years the interest towards the potentialities of this technique for PM analysis has rapidly grown. Surface chemical composition plays an important role in determining the optical properties of aerosol and its reactivity. In this communication we present an XPS surface study of different size fractions of PM, suitably collected using a 10-stage MOUDI-II impactor. Results were compared with chemical analysis of water soluble ions and water soluble carbon in the bulk of the collected particles. Elemental % (conc. > 0.1-1%) surface chemical composition was determined for each size fraction with particular attention to S (SO 42-), Na+, N (NH4+, NO3-, organic nitrogen) and Cl-. Detailed analysis of C1s XPS spectra allowed to distinguish oxygen-containing groups such as carbonylic, carboxylic and carbonate groups. Surface and bulk analyses relevant to size fractions characteristic of coarse and accumulation modes will be reported, considering also a particular case of sea spray accompanied to an intrusion of Saharan Dust.
Application of XPS surface analysis for characterization of size-segregated particulate matter from a urban background site in Lecce
PICCA, ROSARIA ANNA;
2013-01-01
Abstract
Application of X-ray Photoelectron Spectroscopy (XPS) to chemical surface analysis of Particulate Matter (PM) is not yet a routine method in aerosol characterisation. Nonetheless, in the last years the interest towards the potentialities of this technique for PM analysis has rapidly grown. Surface chemical composition plays an important role in determining the optical properties of aerosol and its reactivity. In this communication we present an XPS surface study of different size fractions of PM, suitably collected using a 10-stage MOUDI-II impactor. Results were compared with chemical analysis of water soluble ions and water soluble carbon in the bulk of the collected particles. Elemental % (conc. > 0.1-1%) surface chemical composition was determined for each size fraction with particular attention to S (SO 42-), Na+, N (NH4+, NO3-, organic nitrogen) and Cl-. Detailed analysis of C1s XPS spectra allowed to distinguish oxygen-containing groups such as carbonylic, carboxylic and carbonate groups. Surface and bulk analyses relevant to size fractions characteristic of coarse and accumulation modes will be reported, considering also a particular case of sea spray accompanied to an intrusion of Saharan Dust.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.