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Rectifying Electron-Transport Properties through Stacks of Aromatic Molecules Inserted into a Self-Assembled Cage
Shintaro Fujii1, Tomofumi Tada2, Yuki Komoto1
1†Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8511, Japan.
Journal of the American Chemical Society
|April 23, 2015
Summary
Self-assembled aromatic stacks in molecular cages offer tunable electronic functions. Researchers achieved high conductivity with identical pairs and rectification with different pairs, paving the way for novel molecular electronics.
Area of Science:
- Molecular electronics
- Supramolecular chemistry
- Nanotechnology
Background:
- Aromatic stacks are key components in molecular electronics.
- Self-assembly offers a route to engineer molecular structures.
- Modular components are desirable for tunable electronic functions.
Purpose of the Study:
- To investigate electron-transport properties of single-molecule aromatic stacks.
- To explore the electronic functions of self-assembled cages with modular aromatic pairs.
- To understand the mechanism behind electronic rectification in these systems.
Main Methods:
- Scanning probe microscopy
- Break junction techniques
- Theoretical calculations (e.g., DFT)
- Current-voltage (I-V) characteristics
- Conductance measurements
Main Results:
- Identical aromatic pairs in cages exhibit high conductivity (10^-3 - 10^-2 G0).
- Different aromatic pairs display electronic rectification properties.
- Rectification ratios of 1.4-2 and >10 were observed.
- Rectification is linked to stacking order and localized molecular orbitals.
Conclusions:
- Self-assembled cages provide a platform for modular control of electronic properties.
- Tunable conductivity and rectification are achievable by varying aromatic pairs.
- These findings advance the design of molecular electronic devices.
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