Characterization of an Aerosol Microconcentrator for Analysis Using Microscale Optical Spectroscopies

Area of Science:

• Analytical Chemistry
• Aerosol Science
• Spectroscopy

Background:

• Microscale optical spectroscopies require efficient aerosol microconcentration for effective particle coupling.
• Previous methods for aerosol collection have limitations in efficiency and applicability.

Purpose of the Study:

• To present detailed characterization of a previously developed corona-based aerosol microconcentration technique.
• To evaluate the performance and advantages of this method for microscale spectroscopic applications.

Main Methods:

• Utilized a two-coaxial electrode system with high electrical potential and grounding.
• Employed a one-step charge-and-collect scheme using corona discharge and electrical precipitation.
• Experimentally determined collection efficiency, wall losses, particle deposition density, and spectroscopic sensitivity.

Main Results:

• The corona-based method demonstrated high collection efficiency and particle deposition density.
• Intrinsic spectroscopic sensitivity was experimentally determined for the microconcentrator.
• Performance was found to be superior to filtration, aerodynamic lens impaction, and condensational growth spot collection.

Conclusions:

• Corona-based aerosol microconcentration is highly effective for preparing samples for microscale optical spectroscopies.
• The technique offers significant advantages, including superior performance and suitability for compact, hand-held aerosol analytical instrumentation.