Chemical Identification of Urban Air Particulates in the Environment of Pune City (India) By Raman Spectroscopy

The Raman spectra of urban aerosols were obtained for the characterization of aerosols and a qualitative interpretation of the spectra is presented. An experiment was carried out using a double monochromator with a diffraction grating frequency of 1,800 grooves/mm, a diode laser with a 532-nm wavelength, and with a power source of 25 mW for excitation. The spectra exhibited the presence of various inorganic compounds, including carbonates, sulphates, persulphate of ammonium and potassium, nitrates of ammonium (NH4), potassium and strontium, etc. as well as organic species dominated by the carbon group. In the environmental research, this kind of analytical capability is very useful for the chemical identification of atmospheric aerosol.