Tuning Main Group Element-based Metal-Organic Framework to Boost Electrocatalytic Nitrogen Reduction Under Ambient...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Main group element-based materials are emerging catalysts for electrochemical nitrogen reduction reaction (N2 RR) for ammonia (NH3) production.
• Limited exploration of N2 RR performance and unclear mechanisms hinder their application.

Purpose of the Study:

• Investigate aluminum-based defective metal-organic frameworks (MOFs) for N2 RR.
• Demonstrate the role of defect engineering in enhancing catalytic activity.

Main Methods:

• Synthesized pristine aluminum-fumarate (Al-Fum) MOF using solvothermal reaction.
• Applied defect engineering via solvent-assisted linker exchange to create defective Al sites.
• Utilized density functional theory (DFT) calculations to confirm mechanisms.

Main Results:

• Defective Al-Fum enabled stable and effective electrochemical N2 RR.
• Achieved a high NH3 production rate of 53.9 µg(NH3) h⁻¹ mgcat⁻¹ and Faradaic efficiency of 73.8%.
• DFT calculations confirmed N2 activation and protonation via an alternating associative mechanism at defective Al sites.

Conclusions:

• Defect engineering in Al-based MOFs significantly enhances N2 RR performance.
• Defective Al-Fum shows potential as a promising electrocatalyst for sustainable ammonia synthesis.
• This approach opens avenues for developing main group element-based MOFs for N2 RR and other applications.