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Abstract Plasmas in contact with liquids can degrade organic molecules in a solution, as reactive oxygen and nitrogen species produced in the plasma solvate into the liquid. Immersing small droplets (tens of microns in diameter) in the plasma can more rapidly activate the liquid compared to treating a large volume of liquid with a smaller surface-to-volume ratio. The interactions between a radio frequency glow discharge sustained in He/H2O and a water droplet containing formate (HCOO−aq) immersed in and flowing through the plasma were modeled using a zero-dimensional global plasma chemistry model to investigate these activation processes. HCOO−aqinteracts with OHaq, which is produced from the solvation of OH from the gas phase. The resulting HCOO−aqconcentrations were benchmarked with previously reported experimental measurements. The diameter of the droplet, initial HCOO−aqconcentration, and gas flow rate affect only the HCOO−aqconcentration and OHaqdensity, leaving the OH density in the gas phase unaffected. Power deposition and gas mixture (e.g. percentage of H2O) change both the gas and liquid phase chemistry. A general trend was observed: during the first portion of droplet exposure to the plasma, OHaqprimarily consumes HCOO−aq. However, O2−aq, a byproduct of HCOO−aqconsumption, consumes OHaqonce O2−aqreaches a critically large density. Using HCOO−aqas a surrogate for OHaq-sensitive contaminants, combinations of residence time, droplet diameter, water vapor density, and power will determine the optimum remediation strategy.
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How Does Mg 2+ (aq) Interact with ATP (aq) ? Biomolecular Structure through the Lens of Liquid-Jet Photoemission Spectroscopy
- Award ID(s):
- 1665532
- PAR ID:
- 10514180
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Journal of the American Chemical Society
- Volume:
- 146
- Issue:
- 23
- ISSN:
- 0002-7863
- Format(s):
- Medium: X Size: p. 16062-16075
- Size(s):
- p. 16062-16075
- Sponsoring Org:
- National Science Foundation
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