Improved Interface Charge Transfer and Redistribution in CuO-CoOOH p-n Heterojunction Nanoarray Electrocatalyst for...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electron density modulation is crucial for developing highly active electrocatalysts.
• The oxygen evolution reaction (OER) is a key process in energy storage and conversion.

Purpose of the Study:

• To construct a CuO@CoOOH p-n heterojunction nanoarray electrocatalyst.
• To investigate the mechanism of enhanced OER activity through electron density modulation and surface interactions.

Main Methods:

• In situ anodic oxidation of CuO@CoS_x on copper foam.
• In situ Raman spectroscopy and density functional theory (DFT) calculations.
• Electrochemical performance testing.

Main Results:

• Successfully synthesized CuO@CoOOH p-n heterojunction nanoarrays.
• Demonstrated enhanced electron transfer and OER activity with a low overpotential (186 mV at 10 mA cm^-2).
• Identified surface-adsorbed SO₄^2- as a key intermediate facilitating OER via enhanced OH^- adsorption.

Conclusions:

• The CuO@CoOOH p-n heterojunction effectively enhances OER performance.
• The study provides insights into designing non-noble metal-based p-n heterojunction electrocatalysts.
• The scalable synthesis demonstrates potential for industrial application.