Electron Storage System Based on a Two-Way Inversion of Redox Potentials.

Area of Science:

• Supramolecular Chemistry
• Electrochemistry
• Materials Science

Background:

• Molecular-level multielectron handling is crucial for efficient electrical storage and solar energy harvesting.
• Existing methods often lack efficient ways to store and release multiple electrons reversibly.
• The concept of using chemical bonds as electron reservoirs remains largely unexplored.

Purpose of the Study:

• To introduce and demonstrate the novel concept of "structronics" for molecular-level electrical storage.
• To synthesize and characterize new "super-electrophore" molecules capable of electrochemical bond manipulation.
• To explore the potential of these molecules as three-dimensional counterparts to existing molecular storage systems.

Main Methods:

• Synthesis of two multicomponent "super-electrophores": 1,8-dipyridyliumnaphthalene (2) and its N,N-bridged analogue (3).
• Electrochemical studies to investigate two-electron reduction and oxidation processes.
• Spectroscopic and structural analysis to understand the electronic properties and bond dynamics.

Main Results:

• Demonstrated electrochemical formation and cleavage of a covalent bond within the super-electrophores, utilizing a "super-LUMO" as an electron reservoir.
• The "super-HOMO" (elongated C-C bond) formed upon reduction can be cleaved at an accessible anodic potential, enabling reservoir emptying.
• Exhibited electrochemical hysteresis and chemical reversibility, characteristic of the structronic function.

Conclusions:

• The developed "super-electrophores" successfully implement the structronic concept for molecular electrical storage.
• These molecules offer a new paradigm for energy storage by leveraging reversible bond dynamics.
• Structronic superelectrophores represent a promising three-dimensional extension of established molecular storage systems like methyl viologen.