A nickel-borate nanoarray: a highly active 3D oxygen-evolving catalyst electrode operating in near-neutral water

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Developing efficient and affordable water oxidation catalysts is critical for sustainable energy technologies.
• Existing catalysts often require harsh conditions or are prohibitively expensive.
• There is a pressing need for catalysts that operate effectively under mild conditions.

Purpose of the Study:

• To fabricate and characterize a novel nickel-borate nanoarray supported on carbon cloth (Ni-Bi/CC) for water oxidation.
• To evaluate the catalytic activity and electrochemical durability of the Ni-Bi/CC electrode.
• To explore a cost-effective and high-performance solution for water oxidation catalysis.

Main Methods:

• Fabrication of Ni-Bi/CC via oxidative polarization of NiO/CC in a borate electrolyte (pH 9.2).
• Electrochemical testing of the Ni-Bi/CC as a 3D electrode in 0.1 M potassium borate solution.
• Assessment of catalytic current density, overpotential, and long-term durability.

Main Results:

• The Ni-Bi/CC electrode exhibited superior catalytic activity for water oxidation.
• Achieved a geometrical catalytic current density of 10 mA cm^-2 at an overpotential of 470 mV.
• Demonstrated outstanding long-term electrochemical durability for 25 hours with 100% Faradaic efficiency.

Conclusions:

• The fabricated Ni-Bi/CC serves as a high-performance, cost-effective, and durable electrocatalyst for water oxidation.
• This 3D nanoarray electrode shows significant promise for applications in clean energy conversion.
• The study highlights a viable pathway for developing advanced catalysts under mild conditions.