Hydrolyzed MOFs-Derived IrO_x/Co(OH)₂ for Highly Efficient Electrocatalytic Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Green Energy

Background:

• Electrocatalytic water splitting is key for sustainable hydrogen fuel production.
• Noble metal catalysts are effective but costly and scarce, limiting widespread use.
• Developing efficient, cost-effective alternatives is crucial for advancing green energy technologies.

Purpose of the Study:

• To create a bifunctional electrocatalyst for efficient water splitting using a novel synthesis method.
• To improve the utilization of noble metals in electrocatalysis.
• To develop a stable and high-performance catalyst for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).

Main Methods:

• Synthesized iridium oxide (IrO _x) clusters supported on cobalt hydroxide (Co(OH) ₂) nanosheets on nickel foam (IrO _x/Co(OH) ₂/NF) using a metal-organic framework (MOF)-derived strategy.
• Employed mild, in situ synthesis conditions, avoiding high-temperature treatments.
• Evaluated electrocatalytic performance and stability for overall water splitting.

Main Results:

• The IrO _x/Co(OH) ₂/NF catalyst demonstrated excellent bifunctional activity for OER and HER.
• Achieved low overpotentials of 215 mV for OER and 36.8 mV for HER at 10 mA cm ^-2.
• Exhibited exceptional long-term stability, with minimal degradation over 500 hours (OER), 200 hours (HER), and 100 hours (overall water splitting).

Conclusions:

• The MOF-derived strategy offers a facile and effective route for synthesizing supported cluster electrocatalysts.
• The developed IrO _x/Co(OH) ₂/NF catalyst presents a promising solution for efficient and stable overall water splitting.
• This approach enhances noble metal efficiency, paving the way for practical green energy applications.