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Published on: February 7, 2017
On-surface formation of one-dimensional polyphenylene through Bergman cyclization.
Qiang Sun1, Chi Zhang, Zhiwen Li
1College of Materials Science and Engineering, Key Laboratory for Advanced Civil Engineering Materials (Ministry of Education), Tongji University, Caoan Road 4800, Shanghai 201804, PR China.
Journal of the American Chemical Society
|May 28, 2013
Summary
Researchers fabricated stable, one-dimensional polyphenylene chains on a copper surface using Bergman cyclization and radical polymerization. This advance is key for developing new molecular electronic nanodevices.
Area of Science:
- Materials Science
- Surface Chemistry
- Nanotechnology
Background:
- On-surface fabrication of conjugated nanostructures is crucial for advanced materials.
- Covalently interlinked nanostructures offer high stability and efficient electron transport.
Purpose of the Study:
- To report the on-surface formation of one-dimensional polyphenylene chains.
- To investigate the mechanism of Bergman cyclization and radical polymerization on a metal surface.
Main Methods:
- Utilized scanning tunneling microscopy (STM) for in-situ imaging.
- Employed density functional theory (DFT) calculations for theoretical analysis.
- Confirmed results with ex situ synthesized molecular products.
Main Results:
- Successfully synthesized one-dimensional polyphenylene chains on a Cu(110) surface.
- Demonstrated the pathway involving Bergman cyclization followed by radical polymerization.
- Characterized the nanostructures and confirmed their covalent linkage.
Conclusions:
- On-surface synthesis of polyphenylene chains is achievable via Bergman cyclization and radical polymerization.
- The study provides fundamental insights into surface-mediated organic reactions.
- Findings are significant for the design of molecular electronic nanodevices.
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