Oxide Heterostructure Engineering Drives Stable Lattice Oxygen Evolution for Highly Efficient and Robust Water...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Highly active and stable oxygen evolution reaction (OER) is crucial for green hydrogen production via water electrolysis.
• The lattice oxygen mechanism (LOM) enhances OER activity but typically suffers from low stability.
• Current challenges lie in achieving both high activity and long-term stability in OER electrocatalysts.

Purpose of the Study:

• To develop a CuO_x/Co₃O₄ heterointerface for a stable LOM pathway in OER.
• To investigate interface engineering as a strategy to modulate reaction pathways and enhance catalyst performance.
• To demonstrate the efficacy of this approach for overall water electrolysis in various water conditions.

Main Methods:

• Constructing CuO_x/Co₃O₄ heterointerfaces.
• Utilizing in situ X-ray Absorption Fine Structure (XAFS) to analyze electronic structure and stability.
• Performing electrochemical testing for oxygen evolution reaction (OER) and overall water electrolysis.

Main Results:

• The CuO_x/Co₃O₄ heterointerface successfully shifted the OER pathway to a stable LOM.
• In situ XAFS confirmed the stabilization of cobalt valence states, mitigating corrosion.
• The catalyst demonstrated excellent activity (308 mV at 100 mA cm^-2) and stability (100 h at 500 mA cm^-2) across different water types.

Conclusions:

• Interface engineering is a powerful strategy for activating and stabilizing lattice oxygen in electrocatalysts.
• The CuO_x/Co₃O₄ heterointerface offers a promising solution for efficient and durable water electrolysis.
• This work advances the design of high-performance electrocatalysts for energy and environmental applications, particularly green hydrogen production.