Interface-Engineered Ni(OH)₂ /β-like FeOOH Electrocatalysts for Highly Efficient and Stable Oxygen Evolution...

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Iron-based (oxy)hydroxides are promising electrocatalysts for the oxygen evolution reaction (OER) due to their abundance and low cost.
• However, their practical application is limited by poor OER kinetics on the catalyst surface.

Purpose of the Study:

• To develop a highly efficient and stable electrocatalyst for the OER using iron oxyhydroxide.
• To investigate the role of electroactivation in enhancing the performance of bilayer electrocatalysts.

Main Methods:

• Facile electroactivation treatment of a nickel hydroxide/β-like iron oxyhydroxide (Ni(OH)2/β-like FeOOH) composite.
• Electrochemical characterization of the electrocatalyst's performance for OER.

Main Results:

• The activated Ni(OH)2/β-like FeOOH exhibited an overpotential of 300 mV at 10 mA cm⁻² for OER.
• The electrocatalyst demonstrated excellent stability with no current decay after 50 hours of testing.
• Performance was comparable to state-of-the-art nickel- and cobalt-based electrocatalysts.

Conclusions:

• The metastable tunnel structure of β-like FeOOH facilitates Ni²⁺ ion diffusion, enhancing OER performance during electroactivation.
• This work presents a novel strategy for developing efficient, low-cost electrocatalysts and advances understanding of bilayer electrocatalyst mechanisms for OER.