Efficient Urea Oxidation on MnCO₃/Ni(OH)₂ Nanoflower Arrays Via Interfacial Coupling

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis
• Sustainable Energy

Background:

• Electrochemical urea oxidation reaction (UOR) offers a more energy-efficient alternative to oxygen evolution reaction (OER) for hydrogen production.
• UOR provides dual benefits of energy generation and wastewater remediation.
• Developing highly active and stable UOR electrocatalysts is crucial for practical applications.

Purpose of the Study:

• To develop a novel MnCO3/Ni(OH)2 heterostructured nanoflower array catalyst for enhanced UOR performance.
• To investigate the catalytic activity, stability, and underlying mechanisms of the developed electrocatalyst.
• To provide insights into heterointerface engineering for designing advanced UOR electrocatalysts.

Main Methods:

• Direct growth of MnCO3/Ni(OH)2 heterostructured nanoflower arrays on conductive carbon cloth.
• Electrochemical characterization, including overpotential measurements at various current densities and long-term durability tests.
• Comprehensive material characterization and mechanistic analysis to understand performance enhancements.

Main Results:

• The MnCO3/Ni(OH)2 catalyst demonstrated outstanding UOR catalytic activity and stability.
• Achieved low overpotentials of 90 mV at 10 mA·cm-2 and 167 mV at 200 mA·cm-2.
• Enhanced performance attributed to interfacial electronic redistribution, stabilization of active Ni species, and improved electrode wettability.

Conclusions:

• Heterointerface engineering of MnCO3/Ni(OH)2 is effective in boosting UOR electrocatalytic performance.
• The developed catalyst shows significant potential for sustainable hydrogen generation and wastewater remediation.
• This work highlights the importance of compositional modulation and interface design in creating robust electrocatalysts.