Sodium Cobalt Metaphosphate as an Efficient Oxygen Evolution Reaction Catalyst in Alkaline Solution

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The oxygen evolution reaction (OER) is critical for energy conversion technologies.
• Developing efficient and cost-effective OER catalysts is a significant challenge.
• Precious metal catalysts like RuO2 are effective but expensive.

Purpose of the Study:

• To synthesize and characterize sodium cobalt metaphosphate (NaCo(PO3)3) as an OER catalyst.
• To investigate the catalytic activity of NaCo(PO3)3 prepared via different methods.
• To explore the potential of a novel carbon composite for enhanced OER performance.

Main Methods:

• Synthesis of NaCo(PO3)3 using combustion (Cb) and solid-state (SS) methods.
• Preparation of a carbon composite (NCoM-Cb-Ar) using the combustion-assisted method.
• Electrochemical characterization of catalyst activity in alkaline solution.

Main Results:

• NaCo(PO3)3 exhibits superior OER activity comparable to RuO2.
• The combustion-assisted method provides facile synthesis and one-step carbon composite formation.
• NCoM-Cb-Ar showed exceptionally high catalytic activity with a low overpotential (340 mV) and high mass activity (532 A g-1).

Conclusions:

• Sodium cobalt metaphosphate is a promising non-precious metal OER catalyst.
• The combustion-assisted synthesis route is effective for creating high-performance electrocatalysts.
• Chemical coupling between NaCo(PO3)3 and amorphous carbon enhances OER activity.