Molecular Regulation Based on Functional Trimetallic Metal-Organic Frameworks for Efficient Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Metal-organic frameworks (MOFs) are crystalline porous materials with significant potential in catalysis.
• Achieving molecular regulation of MOF structures for efficient oxygen evolution reaction (OER) electrocatalysts remains a challenge.

Purpose of the Study:

• To design and investigate novel MOF materials for improved OER electrocatalytic performance.
• To explore the structure-property relationships and reaction mechanisms in MOF-based OER electrocatalysts.

Main Methods:

• Synthesized trimetallic MOFs (M3-MOF-BDC) using various metal centers (Fe, Co, Ni, Zn, Mg).
• Introduced functional groups (NH2, OH, NO2, DH) onto the 1,4-benzenedicarboxylic acid (BDC) ligand to create Fe3-MOF-BDC-X series.
• Evaluated OER performance using electrochemical techniques, including overpotential and Tafel slope measurements.

Main Results:

• Fe3-MOF-BDC exhibited the best OER performance among the first series, with an overpotential of 312 mV at 10 mA cm-2.
• Fe3-MOF-BDC-NH2 demonstrated significantly enhanced OER performance, achieving an overpotential of 280 mV at 10 mA cm-2 and a Tafel slope of 45 mV dec-1.
• The Fe3-MOF-BDC-NH2 catalyst outperformed commercial IrO2 and most reported MOFs, showing improved structural stability.

Conclusions:

• The study establishes a strong correlation between MOF structure and OER electrocatalytic properties.
• Functionalization of MOF ligands is a viable strategy to enhance OER performance and stability.
• This work provides a theoretical foundation for designing advanced MOF electrocatalysts for OER.