Reversible surface reconstruction of metal-organic frameworks for durable oxygen evolution reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Metal-organic frameworks (MOFs) are explored as electrocatalysts for the oxygen evolution reaction (OER).
• Controllable and reversible reconstruction of MOFs to generate active catalytic sites for durable OER remains understudied.

Purpose of the Study:

• To investigate the reversible structural transformation of MOFs during OER.
• To develop durable MOF electrocatalysts with enhanced OER performance.

Main Methods:

• Fabrication of orientated Ni-BPM MOF electrodes using a sacrificial lattice-matched-template method.
• In situ Raman and X-ray absorption spectroscopy.
• Density functional theory (DFT) calculations.

Main Results:

• Ni-BPM MOF undergoes surface reconstruction to active γ-NiOOH during OER.
• Reconstructed Ni-BPM exhibits reversible repair during reduction, ensuring durable OER.
• Achieved continuous OER operation at 100 mA cm⁻² for 130 h, followed by 70 h at 500 mA cm⁻².
• Confirmed electronic configuration transformation of Ni sites at the Ni-BPM/γ-NiOOH interface.

Conclusions:

• Demonstrated the reversible structural transformation of MOFs during OER.
• Established a theoretical foundation for developing durable MOF electrocatalysts.
• Ni-BPM MOFs offer superior durability and activity for OER compared to many single Ni-based catalysts.