Surface analysis of air pollutants by XPS: Problems and experiences

Problems and possibilities of air sampling (for surface analytical investigations) are discussed with particular attention to methods that fractionize particles by their sizes. Applications are illustrated by examples using metal and teflon surfaces as samplers. Biological samplers, such as leaves of different trees, proved to be applicable for XPS analysis and showed high sulphate content on their surfaces independent of the location of the three sampling sites. Independently of the methods and sites of air sampling a linear correlation has been found between the quantities of the surface carbon and nitrogen species characterized by their N 1s binding energies close to 400 eV, indicating surface bonds to carbon particles.