Interface Engineering of CoP₃/Ni₂P for Boosting the Wide pH Range Water-Splitting Activity.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical water splitting is crucial for sustainable hydrogen production.
• Developing cost-effective, highly efficient electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) across all pH values remains a significant challenge.

Purpose of the Study:

• To design and investigate novel CoP3/Ni2P heterostructures as advanced electrocatalysts.
• To enhance catalytic performance for both HER and OER in electrochemical water splitting.

Main Methods:

• Density Functional Theory (DFT) calculations to predict catalytic activity.
• High-resolution transmission electron microscopy (HRTEM) for structural analysis.
• X-ray photoelectron spectroscopy (XPS) for electronic state characterization.

Main Results:

• DFT results indicated that CoP3/Ni2P heterostructures significantly improve catalytic performance.
• Experimental characterization confirmed abundant structural defects and optimized electronic states.
• The CoP3/Ni2P catalyst demonstrated superior HER and OER activity and stability in a wide pH range.
• Water splitting achieved 1.557 V at 10 mA cm-2 for over 40 hours, outperforming Pt/C and RuO2 benchmarks.

Conclusions:

• CoP3/Ni2P heterostructures are promising low-cost, high-performance electrocatalysts for water splitting.
• Structural defects and electronic modifications at the heterostructure interface are key to enhanced catalytic activity and durability.
• These findings pave the way for practical applications of electrochemical water splitting in hydrogen production.