Photothermal Switchable Single-Molecule Wires via Donor-Acceptor Side Chains
Jiahong Hu1, Jingtai Li2, Yurou Lang1
1School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Nano Letters
|March 11, 2026
Summary
Researchers developed a novel molecular wire that reversibly switches conductance using light and heat. This breakthrough offers precise control over electron flow for advanced molecular electronics.
Area of Science:
- Molecular electronics
- Organic electronics
- Supramolecular chemistry
Background:
- Precise control of electron distribution in single-molecule electronics remains a challenge.
- Tuning molecular conductance requires advanced strategies for reversible control.
Purpose of the Study:
- To design and demonstrate a single-molecule wire with reversible, state-dependent conductance switching.
- To utilize photoisomerization and thermal relaxation for modulating charge transport.
Main Methods:
- Design of single-molecule wires featuring a carbazole donor and an azobenzene-bridged acceptor side chain.
- Employing photoisomerization of the azobenzene unit to induce a steady state.
- Utilizing scanning tunneling microscopy break junction measurements to assess conductance switching.
Main Results:
- Demonstrated reversible conductance switching between photogenerated and thermally recovered states.
- Photoisomerization partially switches the molecule, with thermal relaxation resetting the initial state.
- Modulation of donor-acceptor interaction, electronic coupling, and conjugation leads to conductance changes.
Conclusions:
- Side-chain engineering with combined photo and thermal stimuli enables reversible, state-dependent control of single-molecule conductance.
- This approach provides valuable insights for developing functional molecular electronic devices.
- Offers a novel strategy for precise charge transport control at the single-molecule level.
