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Updated: Jan 1, 2026
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Preparation of Light-responsive Membranes by a Combined Surface Grafting and Postmodification Process
Published on: March 21, 2014
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Surface grafted agents with various molecular lengths and photochemically active benzophenone moieties
Gaby Nordendorf1, Samuel L Schafforz1, Eireen B Käkel2
1Department of Chemistry, Paderborn University, Warburger Str. 100, 33098 Paderborn, Germany. alexander.lorenz@uni-paderborn.de.
Physical Chemistry Chemical Physics : PCCP
|December 20, 2019
Summary
New benzophenone silane homologues act as photochemically active surface agents for particles and substrates. These agents enable controlled monolayer formation and improved surfactant performance in dispersion fabrication.
Area of Science:
- Materials Science
- Surface Chemistry
- Photochemistry
Background:
- Benzophenone silanes are photochemically active surface functionalizing agents.
- Surface functionalization is crucial for controlling material properties and interfaces.
- Existing surfactants have limitations in dispersion fabrication.
Purpose of the Study:
- Investigate benzophenone silane homologues as surface functionalization agents.
- Evaluate their performance on planar substrates and small particles.
- Assess their efficacy as surfactants in dispersion processes.
Main Methods:
- Synthesis of benzophenone silane homologues with varying aliphatic spacer lengths.
- Surface grafting onto silicon wafers, glass, and ITO-coated glass.
- Characterization using ellipsometry and contact angle measurements.
- Application in wet planetary ball milling for dispersion fabrication.
Main Results:
- Successful monolayer formation on substrates, controllable by spacer length and solution doping.
- Photochemical activity demonstrated by contact angle changes after photo exposure.
- Improved performance as covalently binding surfactants in fabricating dispersions of Fe-doped lithium niobate particles.
- Longer molecular length species yield smaller, functionalized particles.
Conclusions:
- Benzophenone silane homologues are versatile surface functionalization agents.
- Their photochemical activity can be exploited for interface modification.
- They offer superior performance compared to conventional surfactants in dispersion applications.
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