Surface-Decoupled Altitudinal and Azimuthal Triptycene-Fused Tetrapodal Molecular Motors

Area of Science:

• Molecular nanotechnology
• Supramolecular chemistry
• Surface science

Background:

• Development of light-driven molecular motors is crucial for nanoscale machines.
• Triptycene-based platforms offer unique structural properties for motor integration.

Purpose of the Study:

• To design and synthesize novel light-driven molecular motors fused to a tetrapodal platform.
• To investigate the rotational functionality and surface behavior of these motors.

Main Methods:

• Chemical synthesis of triptycene-based tetrapodal platforms with integrated molecular motors.
• Characterization of motor performance including 360° rotation cycles and photoswitching efficiency.
• Assembly of motor monolayers on gold surfaces to assess surface interactions and functionality.

Main Results:

• Successful synthesis of two molecular motor systems with parallel and perpendicular rotational axes.
• Demonstrated complete 360° rotation cycles and efficient photoswitching (∼90% photostationary state at 385 nm).
• Achieved quantitative thermal helix inversion (half-life ∼7 min at 20 °C) and retained functionality on gold surfaces, indicating minimal surface interactions.

Conclusions:

• The synthesized molecular motors exhibit robust performance and controlled rotation.
• The tetrapodal platform effectively minimizes surface interactions, preserving motor functionality.
• These systems hold significant promise for applications in surface-integrated molecular devices and machines.