PdO@CoSe₂ composites: efficient electrocatalysts for water oxidation in alkaline media

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Cobalt selenide (CoSe2) offers abundant active sites and stability for catalysis.
• However, its full potential in water oxidation catalysis remains underexplored.

Purpose of the Study:

• To develop an efficient and stable electrocatalyst for water oxidation.
• To investigate the synergistic effects of doping palladium oxide (PdO) onto cobalt selenide (CoSe2) nanostructures.

Main Methods:

• Synthesis of PdO-doped CoSe2 nanostructures using ultraviolet (UV) light.
• Characterization using X-ray diffraction (XRD), SEM, HRTEM, XPS, and FTIR spectroscopy.
• Electrochemical evaluation of water oxidation performance and durability.

Main Results:

• The composite exhibited a low overpotential of 260 mV at 20 mA cm-2 and a Tafel slope of 57 mV dec-1.
• Characterization revealed heterogeneous morphology, varied oxidation states, and surface defects.
• The catalyst demonstrated 48 hours of durability.

Conclusions:

• The PdO-doped CoSe2 composite is an efficient and stable electrocatalyst for water oxidation.
• Synergistic effects from multi-metal oxidation states, Se edges, and charge transport contribute to low energy demand.
• This development offers a promising alternative for practical energy conversion and storage systems.