Directed Molecular Stacking for Engineered Fluorescent Three-Dimensional Reduced Graphene Oxide and Coronene...

Area of Science:

• Materials Science
• Nanotechnology
• Supramolecular Chemistry

Background:

• Three-dimensional fluorescent graphene frameworks are crucial for applications requiring precise structural and electronic control.
• Existing methods often lack control over porous morphology, limiting practical use in areas like organic electronics and photochemistry.

Purpose of the Study:

• To develop a synthetically accessible approach for creating novel fluorogenic 3D graphene frameworks with tunable porosities.
• To investigate the role of directed aromatic stacking interactions in assembling these new materials.
• To understand the fundamental electronic and energy transfer properties of these engineered architectures.

Main Methods:

• Solvothermal reaction between in-situ reduced graphene oxide (rGO) and functional porphyrins.
• Utilizing porphyrins with perfluorinated aryl groups or hexyl chains to direct framework assembly.
• Characterization using X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Fluorescence Lifetime Imaging Microscopy (FLIM), and theoretical modeling (DFT).
• Single crystal X-ray crystallography to elucidate stacking interactions.

Main Results:

• Successful synthesis of new graphene-based and coronene-based hybrid frameworks (rGOFs) with controlled porous morphologies.
• Demonstrated tunability of pore sizes from the Angstrom to micrometer scale through molecular variations of porphyrins.
• Elucidation of aromatic stacking and host-guest interactions mediated by porphyrins acting as 'molecular glue'.
• Evidence of tunable electronic structures in the nanohybrids based on porosity and inter-sheet distances.

Conclusions:

• A novel, controllable route to 3D fluorescent graphene frameworks with tunable porosity and morphology has been established.
• Functional porphyrins effectively direct the self-assembly of graphene oxide, enabling precise control over material architecture.
• These engineered nanohybrids offer potential for advanced applications in storage devices, selective separation membranes, water purification, and biosensing.