Binary aromatic self-assembled monolayers: electrostatic properties and charge tunneling rates across the molecular
Andika Asyuda1, Xianglong Wan, Michael Zharnikov
1Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, D-69120 Heidelberg, Germany. Michael.Zharnikov@urz.uni-heidelberg.de.
Physical Chemistry Chemical Physics : PCCP
|May 12, 2020
Summary
This study investigated self-assembled monolayers (SAMs) of mercaptobiphenyls on gold. Binary SAMs offer tunable work functions and charge tunneling rates, crucial for molecular electronics.
Area of Science:
- Materials Science
- Surface Chemistry
- Molecular Electronics
Background:
- Self-assembled monolayers (SAMs) are crucial for molecular electronics.
- Understanding the structure-property relationships of SAMs is essential for device performance.
Purpose of the Study:
- To investigate the structure, composition, electrostatic properties, and charge tunneling rates of single-component and binary SAMs.
- To explore the tunability of work function and charge transport in mixed SAMs.
Main Methods:
- Fabrication and characterization of SAMs using non-substituted (H-BPT) and fluorine-substituted (F-BPT) mercaptobiphenyls on Au(111).
- Analysis of SAM structure, composition, work function, and charge tunneling rates.
Main Results:
- All SAMs were well-defined, densely packed, and upright-oriented.
- Binary SAM composition mirrored solution composition.
- Work function was tunable between ~4.3 eV and ~5.2 eV.
- Charge tunneling rate was ~10x higher for H-BPT than F-BPT, with intermediate values for binary SAMs.
Conclusions:
- Binary SAMs provide a controlled method for tuning work function and charge tunneling rates.
- The findings are significant for designing molecular junctions with tailored electronic properties.
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