Stringing Bimetallic Metal-Organic Framework-Derived Cobalt Phosphide Composite for High-Efficiency Overall Water...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Efficient hydrogen production is crucial for the emerging energy conversion technology of water electrolysis.
• Bifunctional catalysts are key for overall water splitting (OWS) through the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).

Purpose of the Study:

• To develop a novel, highly active, and stable bifunctional electrocatalyst for overall water splitting.
• To synthesize CoP nanoparticles embedded in nitrogen-doped carbon materials derived from a ZIF-67/InOF-1 composite.

Main Methods:

• Synthesized a composite of Co-based coordination polymer (ZIF-67) anchored on an indium-organic framework (InOF-1).
• Treated the composite via carbonization and phosphorization to obtain CoP nanoparticles embedded in carbon nanotubes and nitrogen-doped carbon materials (CoP-InNC@CNT).
• Evaluated the electrocatalytic performance for HER and OER in acidic and alkaline media, and for OWS.

Main Results:

• The CoP-InNC@CNT electrocatalyst exhibited high HER activity (153 mV in H2SO4, 159 mV in KOH) and OER activity (270 mV in KOH) at 10 mA cm-2.
• Demonstrated excellent OWS performance with a low overpotential of 1.58 V at 10 mA cm-2 and superior stability.
• The synthesis method ensures uniform growth of catalytic materials on the substrate.

Conclusions:

• CoP-InNC@CNT is a highly effective bifunctional electrocatalyst for overall water splitting.
• The developed material shows significant potential for practical electrochemical hydrogen production.
• The synthesis strategy offers a promising route for fabricating advanced electrocatalysts.