Complexation-induced control of electron propagation based on bounded diffusion through nanopore-tethered ferrocenes

Area of Science:

• Electrochemistry
• Nanotechnology
• Supramolecular Chemistry

Background:

• Ferrocene moieties tethered to nanopores enable electron propagation studies.
• Nanopores derived from diblock copolymers offer controlled architectures.
• Cyclic voltammetry is used to measure faradaic current from bounded diffusion.

Purpose of the Study:

• To investigate complexation-induced control of electron propagation.
• To explore the use of host-guest chemistry for regulating electron transfer.
• To develop novel molecular switches and electrochemical sensors.

Main Methods:

• Covalent tethering of ferrocene moieties onto nanopores (19-24 nm diameter).
• Vertical orientation of nanopores on a gold surface.
• Measurement of faradaic current using cyclic voltammetry in aqueous solutions.

Main Results:

• Faradaic current decreased with increasing beta-cyclodextrin (β-CD) concentration.
• Electron propagation was reversibly inhibited by inclusion complex formation.
• Enhanced partition of β-CD into nanopores led to current decrease at low concentrations (1 × 10⁻⁷ M).

Conclusions:

• Electron propagation in nanopores can be precisely controlled via host-guest complexation.
• The system demonstrates potential for highly sensitive molecular switches and electrochemical sensors.
• This work highlights the utility of nanopore-tethered redox moieties in advanced sensor applications.