Ultrathin Carbon Shell Protecting Copper Sites to Boost Anodic Hydrogen Production via Low-Potential Formaldehyde...

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Copper-based electrocatalysts offer potential for bipolar hydrogen production via aldehyde oxidation.
• Current Cu-based catalysts suffer from insufficient activity and stability for practical applications.
• Formaldehyde oxidation reaction (FOR) coupled with hydrogen evolution reaction (HER) can generate H2 at both electrodes.

Purpose of the Study:

• To enhance the activity and stability of copper electrocatalysts for formaldehyde oxidation.
• To develop a bipolar hydrogen production system utilizing an improved catalyst.
• To investigate the mechanism behind the enhanced catalytic performance.

Main Methods:

• Coating copper spheres with an ultrathin carbon shell.
• Electrochemical characterization of the catalyst's performance in formaldehyde oxidation.
• Experimental and theoretical calculations to elucidate the reaction mechanism.

Main Results:

• The carbon-coated copper catalyst achieved high current density (100 mA cm-2) at a low potential (0.13 V vs RHE) for FOR.
• A bipolar system coupling FOR and HER demonstrated near 100% Faraday efficiency for H2 production.
• The catalyst exhibited stable operation for over 30 hours in a flow cell at a low voltage (0.1 V).

Conclusions:

• The ultrathin carbon shell protects Cu(0) sites, preventing oxidation and ensuring long-term catalyst stability.
• Electron transfer at the Cu/carbon interface lowers the reaction energy barrier, facilitating C-H bond cleavage and H2 generation.
• This work provides a design principle for durable and active copper-based electrocatalysts for hydrogen production.