Efficient water electrolysis with Ce-WO₃@NiCo bifunctional catalysts

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Developing efficient non-precious metal electrocatalysts is crucial for sustainable hydrogen production via water splitting.
• Current challenges include achieving high activity and long-term durability in electrocatalysts.

Purpose of the Study:

• To synthesize and characterize Ce-WO₃@NiCo nanoflower architectures on copper foam for overall water splitting.
• To investigate the role of cerium doping and 3D heterostructures in enhancing catalytic performance.

Main Methods:

• Hydrothermal synthesis and electrodeposition were employed to fabricate the Ce-WO₃@NiCo nanoflower catalysts on copper foam substrates.
• Electrocatalytic activity for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) was evaluated in an alkaline electrolyte.

Main Results:

• The Ce-WO₃@NiCo catalyst demonstrated excellent electrocatalytic activity with low overpotentials (56 mV for HER, 323 mV for OER) at 10 mA cm^-2.
• Overall water splitting required only 1.624 V at 10 mA cm^-2.
• The catalyst exhibited remarkable long-term stability for 72 hours at various current densities (10, 100, and 300 mA cm^-2).

Conclusions:

• Ce-WO₃@NiCo nanoflower architectures provide a promising strategy for developing highly stable, low-cost, self-supported bifunctional electrocatalysts.
• Electronic structure modulation and interface engineering are key to optimizing catalyst performance for water splitting.