Courses: CHEM 231: Analytical Chemistry I (lecture); CHEM 252: Environmental Chemistry; CHEM 332: Analytical Chemistry II (lecture and lab)
Research: My research primarily focuses on reactions at the interface between atmospheric particles and their gaseous surroundings. Particulate matter significantly influences climate change and human health. Despite research aimed at elucidating aerosol formation and growth mechanisms, our current understanding of these processes underestimates atmospheric aerosol mass. Previously, it was thought that atmospheric gas-phase compounds would not interact with the aqueous phase of the aerosol, and no reaction would occur. However, recent research has shown that reactions do occur within the aerosol and possibly at the interface between the aerosol and surrounding gas phase. This could have significant impacts on aerosol mass. It has recently been postulated that photosensitive compounds may play a role in these reactions and aid in aerosol mass growth. These photosensitive compounds may be formed in the aerosol, and therefore be available to undergo reaction. My research is focused on identifying atmospheric compounds which will lead to photosensitized aerosol growth and quantifying the atmospheric importance of this growth.
Research in our lab is carried out in a 300 L Teflon chamber which is surrounded by blacklights to simulate sunlight and is connected to a Scanning Mobility Particle Sizer (SMPS) to allow us to count and size the particles in the chamber. Experiments involve the formation of aerosol containing salts, organic matter, and a possible photosensitizing compound, followed by the introduction of a gas phase alkene in the presence of light. Throughout the experiment, the particle size will be monitored. An increase in particle diameter indicates that a reaction occurred and that some of the gas phase compound has been incorporated into the aqueous particle. Once compounds have been identified as photosensitive (a reaction occurs in the presence of light when they are present in the aerosol), further studies will be performed to determine the mechanism of the reaction and the importance of each photosensitizer to atmospheric aerosol. Experiments are also planned to determine how atmospheric conditions affect these reactions.
* undergraduate student coauthors