Rational engineering of a tetrametal-organic framework for enhanced electrocatalytic oxygen evolution.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient and affordable multicomponent electrocatalysts is essential for advancing water oxidation processes.
• Metal-organic frameworks (MOFs) are attractive electrocatalysts due to their adaptable structures and compositions.

Purpose of the Study:

• To synthesize and evaluate tetrametallic NiFeCoV-MOF-74 nanospheres as electrocatalysts for the oxygen evolution reaction (OER).
• To investigate the structural properties and electrochemical performance of the novel MOF-based catalyst.

Main Methods:

• Facile one-step solvothermal synthesis of tetrametallic NiFeCoV-MOF-74 nanospheres.
• Electrochemical characterization including overpotential, Tafel slope, and long-term stability testing.
• Advanced spectroscopic analyses such as X-ray photoelectron spectroscopy (XPS) and in situ Raman spectroscopy.

Main Results:

• The NiFeCoV-MOF-74 catalyst exhibited superior OER performance with a low overpotential (266 mV at 10 mA cm^-2) and an excellent Tafel slope (32.7 mV dec^-1).
• The catalyst demonstrated remarkable stability, maintaining activity for 100 hours at 100 mA cm^-2.
• Electrochemical analysis identified NiOOH and CoOOH as the active sites, with synergistic effects from Ni, Fe, Co, and V enhancing OER kinetics.

Conclusions:

• Tetrametallic NiFeCoV-MOF-74 nanospheres are highly effective electrocatalysts for the oxygen evolution reaction.
• The synergistic interplay between multiple metal elements in MOFs significantly boosts catalytic activity and stability.
• This research underscores the potential of designing advanced multimetallic MOFs for efficient electrochemical energy conversion systems.