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Supramolecular assembly on surfaces: manipulating conductance in noncovalently modified mesoscale structures
Grace M Credo1, Andrew K Boal, Kanad Das
1Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
Journal of the American Chemical Society
|August 1, 2002
Summary
Researchers controlled molecular self-assembly and electronic properties using hydrogen bonding. Complementary molecules tuned surface structure conductance, increasing or decreasing it as observed with scanning tunneling microscopy.
Area of Science:
- Surface science
- Supramolecular chemistry
- Molecular electronics
Background:
- Noncovalent self-assembly is crucial for creating ordered molecular structures on surfaces.
- Controlling electronic properties at the nanoscale requires precise molecular arrangement.
- Hydrogen bonding offers a versatile tool for directing molecular assembly through specific interactions.
Purpose of the Study:
- To investigate the use of complementary hydrogen bonding for controlling surface mesostructure formation.
- To tune the electronic properties, specifically current-voltage characteristics, of patterned surface assemblies.
- To demonstrate the ability to modulate conductance in self-assembled monolayers using molecular recognition.
Main Methods:
- Fabrication of a chemically defined patterned surface region for molecular assembly.
- Utilizing molecules with complementary hydrogen bonding functionalities for self-assembly.
- Characterization of the self-assembled structures and their electronic properties using scanning tunneling microscopy (STM).
- Measurement of current-voltage (I-V) properties of the patterned regions.
Main Results:
- Successful self-assembly of molecules into a defined surface mesostructure guided by hydrogen bonding.
- Demonstrated modulation of conductance within the surface-bound mesoscale structures.
- Achieved both increases and decreases in observed conductance by altering the functionalities of the complementary moieties.
- Correlated molecular structure and recognition with changes in electronic transport properties.
Conclusions:
- Complementary hydrogen bonding is an effective strategy for controlling noncovalent self-assembly and electronic properties of surface mesostructures.
- The ability to tune conductance by designing specific molecular interactions opens avenues for molecular electronics.
- Scanning tunneling microscopy is a powerful technique for visualizing and characterizing these nanoscale electronic phenomena.
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