Multilayered Molybdate Microflowers Fabricated by One-Pot Reaction for Efficient Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing high-performance, cost-effective, and rapidly produced bifunctional electrocatalysts for overall water splitting remains a significant challenge.
• Existing catalysts often struggle to meet the demands for efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) simultaneously.

Purpose of the Study:

• To synthesize and characterize a novel self-supported bifunctional electrocatalyst for overall water splitting.
• To investigate the electrocatalytic performance and reaction mechanism of the developed material.

Main Methods:

• Facile hydrothermal synthesis of cobalt-doped ammonium lanthanum molybdate on nickel foam (Co-ALMO@NF).
• Electrocatalytic performance testing for HER and OER in alkaline medium.
• Density functional theory (DFT) calculations to elucidate reaction mechanisms.

Main Results:

• Co-ALMO@NF exhibits remarkable electrocatalytic activity, requiring only 349 mV for HER and 341 mV for OER to reach 600 mA cm⁻².
• Achieved a low cell voltage of 1.52 V at 10 mA cm⁻² with excellent long-term stability in a two-electrode configuration.
• DFT calculations indicate favorable Mo sites for HER and Co's role in accelerating OER by reducing surface adsorption.

Conclusions:

• The Co-ALMO@NF material demonstrates superior bifunctional electrocatalytic activity and stability for overall water splitting.
• Structural design, including lattice defects and conductive channels, is crucial for enhancing electrocatalyst performance.
• This work offers a promising pathway for designing efficient and durable electrocatalysts for clean energy applications.