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Abstract Enhancing mass transport of reactive species and photons at the plasmaliquid interface is an important consideration for the scaling of atmospheric pressure plasmas studied in the laboratory to real-world applications. It is well-known that the introduction of turbulence at any interface will enhance mixing by enhancing species uptake from the gas phase to the liquid phase by surface renewal processes, entrainment, bubbles and surface area modification. The goal of this work is to isolate surface effects associated with turbulence from the multitude of turbulent transport enhanced processes by artificially introducing surface perturbations using Faraday waves. Experiments were also conducted to determine decoloration rate constants of a model contaminant (methylene blue) as a function of both discharge features and hydrodynamics (Faraday surface wavelengths). The local plasma ionization wave at the interfacial structure was modeled and compared to experiments. Interestingly, it was found in experiments that plasma in contact with the water also generated capillary waves thus modifying the surface as well. Plasma ionization waves in combination to acoustic driven Faraday waves adds to the complexity of interpreting the effects of, for example, surface area increases, due to these complex coupled phenomenon. Local plasma ionization wave structure appears to be modified (increased propagation distance) when the liquid is perturbed, leading to increased contact of the liquid water surface with reactive species. Along with interfacial surface area growth, nonlinear convective transport is also increased with perturbations, leading to the general realization that acoustic perturbations can improve transport and thus decoloration of the model contaminant dye.
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Recent Insights Into Interfacial Transport and Chemical Reactions of Plasma‐Generated Species in Liquid
ABSTRACT The chemistry of plasma–liquid interactions involves a complex interplay of physical and chemical processes at the plasma–liquid interface. These interactions give rise to the generation, transport, and transformation of various reactive species. Since the publication of the Lorenz Roadmap in 2016, significant progress has been made in understanding the interfacial transport and coupled reactions of plasma‐generated species with inorganic and organic compounds. However, critical aspects of plasma–liquid chemistry and mass transfer still require further investigation. This review summarizes recent work on processes at the plasma–liquid interface and the coupled reactions in the liquid phase. We highlight key findings related to the involvement of O atoms, H radicals, solvated electrons, photons, and nitrogen‐derived species at the interface and within the bulk liquid.
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- Award ID(s):
- 2318494
- PAR ID:
- 10630150
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Plasma Processes and Polymers
- Volume:
- 22
- Issue:
- 1
- ISSN:
- 1612-8850
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/ppap.202400207
