Amorphization enabled deep self-reconstruction of bimetallic metal-organic frameworks for efficient and robust oxygen...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Metal-organic frameworks (MOFs) offer tunable structures for catalysis.
• Developing efficient and stable electrocatalysts for the oxygen evolution reaction (OER) is crucial for water splitting.
• Self-reconstruction in MOFs can lead to enhanced catalytic properties.

Purpose of the Study:

• To develop a novel amorphization strategy for self-reconstruction in bimetallic MOFs.
• To design high-performance electrocatalysts for the oxygen evolution reaction (OER).
• To investigate the mechanism of MOF reconstruction and its impact on OER activity.

Main Methods:

• Synthesis of bimetallic tetrathiafulvalene tetrabenzoate (H4TTFTB) MOFs on nickel foam (NF).
• Induction of amorphization and self-reconstruction via a specific treatment.
• Electrochemical characterization (overpotential, stability) and operando Raman spectroscopy.
• Density functional theory (DFT) calculations to understand the electronic structure and reaction mechanism.

Main Results:

• The optimized Co3Fe1-TTFTB@NF catalyst achieved low OER overpotentials (228 mV at 10 mA cm-2) and excellent stability (200 h at 100 mA cm-2).
• Amorphization engineering promoted reconstruction into a highly active (Co3Fe1)OOH phase.
• Fe incorporation was found to lower oxygen vacancy formation energy, facilitating reconstruction.
• The reconstructed (Co3Fe1)OOH exhibited a low theoretical OER overpotential of 0.68 V.

Conclusions:

• Amorphization engineering is an effective strategy for designing self-reconstructing MOFs into advanced OER electrocatalysts.
• The study demonstrates a pathway to highly efficient and stable MOF-derived catalysts for alkaline water oxidation.
• This approach provides a general design principle for developing next-generation water splitting catalysts.