Confining H₃PO₄ network in covalent organic frameworks enables proton super flow

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Developing stable, high-performance porous materials is challenging, especially for proton transport applications.
• Proton-transporting materials are critical for sensing, catalysis, and energy conversion/storage.

Purpose of the Study:

• To synthesize a dually stable covalent organic framework (COF) with aligned nanochannels for enhanced proton transport.
• To investigate the stabilization mechanisms of the pore structure and proton networks within the COF.

Main Methods:

• Topology-guided synthesis of an imine-bonded COF.
• Utilizing linker-induced hyperconjugation and inductive effects for pore stabilization.
• Confining and stabilizing phosphoric acid (H3PO4) within nanochannels via hydrogen bonding.

Main Results:

• The synthesized COF features dense, aligned one-dimensional nanochannels.
• Proton super-flow rates were enhanced by 2-8 orders of magnitude compared to analogues.
• Temperature profiles and molecular dynamics showed proton hopping with low activation energies and high mobility.

Conclusions:

• The topology-guided synthesis approach yields highly stable and efficient proton-conducting materials.
• The designed COF structure effectively stabilizes proton networks, enabling super proton flow.
• This work offers a promising pathway for advanced materials in energy and catalysis applications.