Iron-Based Metal-Organic Framework System as an Efficient Bifunctional Electrocatalyst for Oxygen Evolution and...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient and sustainable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is crucial for overall water splitting.
• Current electrocatalysts often face challenges in terms of efficiency, stability, and cost.

Purpose of the Study:

• To synthesize and characterize a series of novel metal-organic frameworks (MOFs) as multifunctional electrocatalysts for HER and OER.
• To investigate the enhanced electrocatalytic performance and stability of these MOFs in alkaline media.

Main Methods:

• Synthesis of Fe2M-MOF (M = Fe, Co, Ni, Zn, Mn) using a simple and mild condition.
• Electrocatalytic performance evaluation for OER and HER, including overpotential and Tafel slope measurements.
• Long-term stability tests under working conditions.

Main Results:

• The Fe2Co-MOF catalyst exhibited excellent OER performance with an overpotential of 339 mV at 10 mA cm⁻², surpassing commercial IrO2.
• The Fe2Zn-MOF catalyst demonstrated outstanding HER activity with an overpotential of 221 mV at 10 mA cm⁻².
• All synthesized MOFs showed good long-term stability for electrocatalytic applications.

Conclusions:

• A novel series of Fe2M-MOFs were successfully synthesized and demonstrated superior bifunctional electrocatalytic activity for HER and OER.
• The strategy of incorporating redox-active metal centers and organic linkers in MOFs provides an effective pathway for designing advanced electrocatalysts.
• These MOFs hold significant promise for future energy conversion applications, particularly in overall water splitting.