Doping β-CoMoO₄ Nanoplates with Phosphorus for Efficient Hydrogen Evolution Reaction in Alkaline Media

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Efficient and economical electrocatalysts are crucial for large-scale hydrogen production through water electrolysis.
• Transition-metal oxides, despite their abundance, are generally poor electrocatalysts for the hydrogen evolution reaction (HER).
• Developing novel materials to overcome these limitations is an active area of research.

Purpose of the Study:

• To investigate the potential of phosphorus-doped β-CoMoO₄ nanoplates as active electrocatalysts for HER.
• To elucidate the underlying mechanisms responsible for enhanced HER activity in doped materials.
• To establish a new strategy for improving the electrocatalytic performance of transition-metal oxides.

Main Methods:

• Synthesis of phosphorus-doped β-CoMoO₄ nanoplates.
• Electrochemical characterization, including overpotential measurements for HER.
• Theoretical calculations (e.g., density functional theory) to understand electronic structure and adsorption energies.

Main Results:

• Phosphorus doping significantly enhances the electrocatalytic activity of β-CoMoO₄ for HER.
• P-doped β-CoMoO₄ requires an overpotential of only 138 mV to achieve a current density of 10 mA cm⁻² in 1 M KOH.
• Enhanced electrical conductivity and optimized hydrogen adsorption free energy are identified as key factors for improved activity.

Conclusions:

• Phosphorus doping transforms β-CoMoO₄ into a highly active HER electrocatalyst.
• The doped material exhibits performance competitive with state-of-the-art electrocatalysts, approaching that of commercial Pt/C.
• This study presents a promising new approach for designing efficient and cost-effective electrocatalysts for hydrogen production.