Oxygen vacancy-confined CoMoO₄@CoNiO₂ nanorod arrays for oxygen evolution with improved performance

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient electrocatalysts for water oxidation is crucial for renewable energy technologies.
• Supported nanostructures offer enhanced surface area and catalytic activity.

Purpose of the Study:

• To synthesize CoMoO4@CoNiO2 nanostructures on Ni foam for electrocatalytic water oxidation.
• To investigate the role of oxygen vacancies in enhancing catalytic performance.

Main Methods:

• Hydrothermal synthesis of CoMoO4@CoNiO2 nanostructures on Ni foam.
• Electrocatalytic water oxidation performance testing.
• X-ray photoelectron spectroscopy (XPS) for characterization.
• Density Functional Theory (DFT) calculations.

Main Results:

• Successfully synthesized CoMoO4@CoNiO2 nanostructures in situ on Ni foam.
• Achieved high turnover frequency (TOF) for electrocatalytic water oxidation, among the highest reported for supported catalysts.
• Demonstrated a correlation between oxygen vacancy density and improved electrocatalytic performance.

Conclusions:

• The novel CoMoO4@CoNiO2 nanostructures are highly effective electrocatalysts for water oxidation.
• Oxygen vacancies significantly boost electrocatalytic activity by enhancing reactant adsorption and modulating electronic structure.
• This work provides insights into designing advanced supported catalysts for energy applications.