Film formation from plasma-enabled surface-catalyzed dehalogenative coupling of a small organic molecule
Hugo Hartl1, Yanru Guo1,2, Ken Ostrikov1,3
1School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology (QUT) 2 George Street Brisbane QLD Australia 4000 jennifer.macleod@qut.edu.au.
RSC Advances
|May 6, 2022
Summary
A novel plasma-based method enables direct surface coating fabrication via dehalogenative coupling of aromatic molecules. This technique allows control over film properties like chemistry, morphology, and wettability.
Area of Science:
- Materials Science
- Surface Chemistry
- Plasma Physics
Background:
- Surface coatings are crucial for modifying material properties.
- Traditional methods for fabricating coatings can be complex and energy-intensive.
- Developing direct, controlled methods for surface functionalization is an ongoing challenge.
Purpose of the Study:
- To demonstrate a new pathway for direct on-surface fabrication of surface coatings.
- To investigate the use of atmospheric pressure plasma for dehalogenative coupling reactions.
- To explore the control over film characteristics by varying plasma parameters.
Main Methods:
- Utilized a room temperature, atmospheric pressure dielectric barrier discharge (DBD) plasma.
- Applied pure nitrogen plasma to small aromatic molecules on a catalytic surface.
- Analyzed fabricated films using optical and helium ion microscopy (HIM), X-ray photoelectron spectroscopy (XPS), optical profilometry, and contact angle measurements.
Main Results:
- Successfully fabricated surface coatings through plasma-induced dehalogenative coupling.
- Demonstrated control over film chemistry, morphology, and roughness by adjusting plasma power and duration.
- Achieved tunable surface wettability, with high-dose plasmas resulting in hydrophobic surfaces (contact angles up to 130°).
Conclusions:
- Plasma-assisted dehalogenative coupling offers a direct and controllable route for surface coating fabrication.
- The developed method allows for tailoring surface properties for specific applications.
- This approach presents a promising alternative to conventional coating techniques.
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