Tuning Conductance in BODIPY-Based Single-Molecule Junctions

Area of Science:

• Molecular electronics
• Organic electronics
• Single-molecule electronics

Background:

• Boron-dipyrromethene (BODIPY) molecules are promising for optoelectronic applications.
• Understanding charge transport at the single-molecule level is crucial for developing molecular devices.
• The scanning tunneling microscope-break junction (STM-BJ) technique allows direct measurement of molecular conductance.

Purpose of the Study:

• To investigate charge transport properties of BODIPY-based molecules.
• To demonstrate the feasibility of using BODIPY cores in molecular junctions.
• To explore the effect of linker modification on molecular conductance.

Main Methods:

• Utilized the scanning tunneling microscope-break junction (STM-BJ) technique.
• Synthesized and characterized three BODIPY-based molecules with varying aurophilic linkers at the 2,6-positions.
• Performed density functional theory (DFT)-based calculations, including a novel correction for transmission predictions.

Main Results:

• Successfully measured molecular conductance through the BODIPY core by incorporating aurophilic linkers.
• Demonstrated that varying linker groups systematically modulates frontier molecular orbital energies.
• Observed fine-tuning of charge transport behavior through linker modification.
• DFT calculations supported experimental findings and provided insights into transport mechanisms.

Conclusions:

• Established the viability of BODIPY-based molecules for constructing molecular junctions.
• Showcased the ability to tune molecular conductance via linker engineering.
• Laid the foundation for future research into single-molecule optoelectronic properties of BODIPY systems.