Quantum mechanics

Engineering

Fabrication

Electrochemistry

Materials science

Proton transport

Proton

Covalent organic framework

Biochemistry

Chemical engineering

Porosity

Physical chemistry

Alternative medicine

Hydrogen

Physics

Proton exchange membrane fuel cell

Nanotechnology

Organic chemistry

Membrane

Conductivity

Composite material

Medicine

Chemistry

Electrode

Covalent bond

Thermal conduction

Electrolyte

Pathology

Angewandte Chemie International Edition

Developing new materials for the fabrication of proton exchange membranes (PEMs) for fuel cells is of great significance. Herein, a series of highly crystalline, porous, and stable new covalent organic frameworks (COFs) have been developed by a stepwise synthesis strategy. The synthesized COFs exhibit high hydrophilicity and excellent stability in strong acid or base (e.g., 12 m NaOH or HCl) and boiling water. These features make them ideal platforms for proton conduction applications. Upon loading with H3 PO4 , the COFs (H3 PO4 @COFs) realize an ultrahigh proton conductivity of 1.13×10-1 S cm-1 , the highest among all COF materials, and maintain high proton conductivity across a wide relative humidity (40-100 %) and temperature range (20-80 °C). Furthermore, membrane electrode assemblies were fabricated using H3 PO4 @COFs as the solid electrolyte membrane for proton exchange resulting in a maximum power density of 81 mW cm-2 and a maximum current density of 456 mA cm-2 , which exceeds all previously reported COF materials.

Combined Intrinsic and Extrinsic Proton Conduction in Robust Covalent Organic Frameworks for Hydrogen Fuel Cell Applications