2D NiFe₂O₄/Ni(OH)₂ Heterostructure-Based Self-Supporting Electrode With Synergistic Surface/Interfacial Engineering...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Industrial demand for efficient overall water splitting necessitates improved oxygen evolution reaction (OER) electrocatalysts.
• Current electrocatalysts often lack a balance of low cost, high effectiveness, and durability.

Purpose of the Study:

• To develop a novel, low-cost, highly effective, and durable electrocatalyst for the oxygen evolution reaction (OER).
• To engineer a 2D NiFe2O4/Ni(OH)2 heterostructure with enhanced interfacial properties for water splitting.

Main Methods:

• A facile confined strategy was employed to construct 2D NiFe2O4/Ni(OH)2 heterostructures on a self-supporting electrode.
• Surface-interfacial coengineering was utilized to create abundant and ultrastable interfaces.
• A high Ni/Fe molar ratio promoted the simultaneous formation of spinel oxide and hydroxide phases.

Main Results:

• The NiFe2O4/Ni(OH)2 interface exhibited strong electronic interactions, promoting the formation of crystalline-amorphous NiOOH active sites.
• A stable catalyst-collector interface facilitated efficient electron transfer and oxygen molecule transport.
• The 2D NiFe2O4/Ni(OH)2@CP electrode achieved a low OER overpotential (389 mV) and long-term stability (12 h at 1 A cm-2).

Conclusions:

• The engineered 2D NiFe2O4/Ni(OH)2 heterostructure demonstrates superior OER performance.
• This work offers a novel and efficient strategy for fabricating cost-effective electrocatalysts for electrochemical energy conversion devices.