Chemical characterization of environmental and industrial particulate samples†

Abstract

The characterization of particles, especially aerosol particles, is of great importance to many scientific fields. A relevant brief overview is given. A rigorous scheme of sampling and in-depth characterization of particulate samples has been developed in the authors’ laboratories and by collaborative groups, including investigations by the following techniques: total reflection X-ray fluorescence spectrometry for quantitative bulk characterization; solid-state speciation by valence band X-ray spectrometry using electron microprobe or Mössbauer spectrometry (only bulk particle characterization possible); scanning electron microscopy and electron probe microanalysis for automatic semiquantitative single particle characterization of particles ≥0.5 µm; transmission electron microscopy for semiquantitative single particle characterization of particles with diameters down to 10 nm; high resolution-scanning electron microscopy, which is also capable of characterizing particles morphologically and qualitatively down to 10 nm in diameter; secondary ion mass spectrometry for the study of trace elemental distributions and isotopic ratios in particles with diameters above 1 µm. It is the aim of this paper to show the advantages and characteristics of this scheme of analysis to match today′s requirements for topochemical methods of analysis. For this purpose a short overview of these methods for particle characterization is also presented.