Collaborative research: chamber studies of volatile organic compound oxidation across a range of organic peroxy radical conditions

Aerodyne Research Inc. received a $272,363 Project Grant award dated August 15, 2025, from the National Science Foundation's Division of Atmospheric and Geospace Sciences under the Geosciences program (CFDA 47.050). The project, titled "Collaborative Research: Chamber Studies of Volatile Organic Compound Oxidation Across a Range of Organic Peroxy Radical Conditions," extends through July 31, 2028, and will deliver fundamental research services focused on understanding the chemical oxidation mechanisms of non-methane volatile organic compounds (VOCs) in the atmosphere. The research will generate controlled chamber study data and analysis examining how organic peroxy radicals (RO2) interact with model VOCs including isoprene, monoterpenes, and aromatics across a comprehensive range of atmospheric conditions.

The primary deliverables include experimental findings on the formation mechanisms and yields of secondary atmospheric species such as ozone, formaldehyde, and secondary organic aerosol, along with validation of predictive capabilities of state-of-the-art chemical mechanisms used in atmospheric modeling. The project will support educational outcomes through training of graduate and undergraduate students. No sub-awards are planned for this grant. This research directly supports the NSF Geosciences program's mission to advance fundamental knowledge of the integrated Earth system through expanded understanding of atmospheric sciences and natural processes.

Abstract

This project seeks to better understand what chemical species result from the oxidation of non-methane volatile organic compounds. Model-informed chamber studies will be conducted during which the reactivity of organic peroxy radicals will be carefully controlled and monitored. A better understanding of volatile organic compound oxidation in the atmosphere will lead to better predictions of the formation of secondary atmospheric species such as ozone, formaldehyde, and secondary organic aerosol, species that contribute to degraded air quality. The major scientific objectives of the project are: (1) to better understand the formation mechanism and yields of these key secondary species, across the range of organic peroxy radicals (RO2) conditions found in the atmosphere; and (2) to understand the extent to which these secondary species are accurately predicted using state-of-the-art chemical mechanisms or approximated from measurements of extreme RO2 conditions, in which RO2 reacts only with no or only with HO2, simplifying the product distributions considerably. Chamber experiments will cover a number of model volatile organic compounds (isoprene, monoterpenes, aromatics, and others), across the full range of RO2 conditions found in the global atmosphere, a much wider range than previously studied. The project will support the training of both graduate and undergraduate students. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.- subawards are not planned for this award.