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On-Surface Ullmann-Type Coupling Reactions of Aryl Halide Precursors with Multiple Substituted Sites
Qiwei Liu1, Yuhong Gao1, Chi Zhang1
1Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
On-surface synthesis using Ullmann-type coupling enables precise fabrication of low-dimensional nanostructures. This review details carbon-based nanostructure preparation from aryl halides, highlighting applications in molecular electronics.
Area of Science:
- Materials Science
- Surface Chemistry
- Nanotechnology
Background:
- On-surface synthesis is key for creating precise electronic devices.
- Ullmann-type coupling offers efficient and programmable fabrication of nanostructures.
Purpose of the Study:
- To review progress in preparing carbon-based nanostructures via on-surface Ullmann-type coupling.
- To categorize nanostructures based on halogen substitution sites of precursors.
- To analyze and compare the characteristics of resulting nanostructures.
Main Methods:
- Utilizing Ullmann-type coupling reactions on aryl halide precursors.
- Employing in situ characterization techniques for reaction monitoring.
- Categorizing precursors by halogen substitution patterns (para, meta, ortho, peri, bay regions).
Main Results:
- Demonstrated high structural diversity in carbon-based nanostructures.
- Showcased significant potential for applications in molecular electronics.
- Provided a systematic analysis of nanostructures derived from various halogen substitution sites.
Conclusions:
- On-surface Ullmann-type coupling is a powerful method for fabricating diverse carbon nanostructures.
- Precise control over precursor halogenation enables tailored nanostructure properties.
- These nanostructures hold promise for advanced molecular electronic devices.
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