Modulating the electronic structure of NiFe layered double hydroxide via anion engineering for enhanced oxygen...

Area of Science:

• Electrochemistry
• Materials Science
• Sustainable Energy

Background:

• Alkaline water electrolysis is key for hydrogen production.
• Nickel-iron layered double hydroxide (NiFe LDH) is a promising oxygen evolution reaction (OER) catalyst.
• Improving NiFe LDH active species modulation is crucial for industrial applications.

Purpose of the Study:

• To develop a novel NiFe LDH electrocatalyst using anion engineering.
• To enhance the performance of NiFe LDH for alkaline water electrolysis.
• To investigate the impact of anion modification on catalytic activity and stability.

Main Methods:

• Facile anion engineering strategy.
• Synthesis of novel NiFe LDH.
• Electrochemical characterization including overpotential and stability testing.
• Analysis of electronic structure and charge transport.

Main Results:

• Sulfate induction effectively withdraws electrons, increasing Ni and Fe oxidation states.
• Modified NiFe LDH exhibits enhanced charge transport and optimized adsorption energy.
• Achieved a low OER overpotential of 223 mV, surpassing commercial benchmarks.
• Demonstrated excellent stability (>70 h at 100 mA cm⁻²) in alkaline and seawater electrolysis.

Conclusions:

• Anion engineering is a viable strategy for designing efficient OER catalysts.
• The novel NiFe LDH shows significant potential for large-scale hydrogen production.
• Synergistic effects of carbonate and sulfate anions enhance stability in diverse conditions.