Studies on Secondary Aerosol Formation Using Chemical Ionization Mass Spectrometry

Abstract

Understanding the formation processes of secondary aerosols in the atmosphere requires quantitative information on their precursor gaseous species. This article describes the application of the chemical ionization mass spectrometry (CIMS) including proton transfer reaction mass spectrometry (PTR-MS) to real-time and highly selective measurement of gaseous species involved in the secondary aerosol formation. The principles and characteristics of CIMS are presented, followed by the representative studies using CIMS in measuring both inorganic and organic gaseous species which may play an important role in the secondary aerosol formation. Finally, future prospects including the application of CIMS and PTR-MS to analysis of the aerosol chemical composition are presented.