Sustainable Design for High-Performance Hybrid Proton Exchange Membranes With a Proton-Conducting Metal Organic...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) are emerging as advanced materials for proton conductors.
• Proton exchange membranes (PEMs) are crucial components in fuel cells (FCs).
• Developing high-performance, durable PEMs is essential for efficient fuel cell technology.

Purpose of the Study:

• To synthesize a novel mixed-ligand MOF for proton conduction.
• To create composite proton exchange mixed matrix membranes (PEMMMs) using the MOF.
• To evaluate the proton conductivity of the MOF and its composite membranes.

Main Methods:

• Synthesis of a novel mixed-ligand MOF, {[Zn2(4-pa)(5-sip)(H2O)3]·(H2O)3}n (1), using Zn(II), 4-picolylamine (4-pa), and sodium 5-sulfoisophthalate (5-sip).
• Incorporation of MOF 1 into a polyvinylidene fluoride (PVDF) and Polyvinylpyrrolidone (PVP) matrix to form PEMMMs (1@MMM-XX).
• Proton conductivity measurements at 80°C and 100% relative humidity.

Main Results:

• Compound 1 exhibited a proton conductivity of 3.44 × 10^-3 S.cm^-1.
• The 1@MMM-40 membrane (40 wt.% MOF 1) achieved a conductivity of 2.81 × 10^-2 S.cm^-1, an ~8-fold increase over pure MOF 1.
• The 1@MMM-40 membrane showed a 16-fold enhancement compared to the blank PVDF/PVP film.

Conclusions:

• The novel MOF and its composite membranes demonstrate significantly enhanced proton conductivity.
• The developed PEMMMs show great potential for high-performance fuel cell applications.
• The incorporation of MOFs into polymer matrices is an effective strategy for improving PEM performance.