Reversing the Conductance Evolution of Azobenzene Derivatives in Photoisomerization

Area of Science:

• Molecular electronics
• Organic electronics
• Supramolecular chemistry

Background:

• Azobenzene derivatives are promising for light-controlled switches.
• Electrode coupling often causes a quenching effect, limiting performance.
• Designing molecules to insulate functional cores is crucial.

Purpose of the Study:

• Synthesize novel azobenzene derivatives (TATA-TMA and TATA-TA) for improved light-controlled electronic switches.
• Investigate the impact of a large TATA base and decoupling groups on molecular conductance.
• Explore the mechanism behind opposite conductance evolution trends in photoisomerization.

Main Methods:

• Chemical synthesis of TATA-TMA and TATA-TA azobenzene derivatives.
• Incorporation of a large TATA base to increase intermolecular distance.
• Introduction of decoupling groups to insulate the azobenzene core from electrodes.
• Conductance measurements during trans-cis photoisomerization.

Main Results:

• Synthesized azobenzene derivatives exhibit enhanced conductance switch ratios by one order of magnitude.
• The TATA base and decoupling groups effectively insulate the azobenzene core.
• TATA-TMA and TATA-TA show opposite conductance evolution trends during photoisomerization.
• The study elucidates the mechanism for controllable switching direction.

Conclusions:

• Novel azobenzene derivatives with enhanced photoresponsive switching are developed.
• The design strategy effectively mitigates electrode quenching effects.
• Controllable switching directionality is achieved, offering a new design paradigm for molecular electronics.