Ultrathin cobalt-manganese layered double hydroxide is an efficient oxygen evolution catalyst

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Cost-effective solar fuel production necessitates efficient and stable oxygen evolution reaction (OER) catalysts.
• Earth-abundant alternatives to precious metal catalysts are crucial for widespread adoption.

Purpose of the Study:

• To develop and characterize ultrathin cobalt-manganese layered double hydroxide (CoMn LDH) nanoplates as an OER catalyst.
• To evaluate the activity, stability, and performance enhancement of CoMn LDH for OER.

Main Methods:

• One-pot coprecipitation method at room temperature for CoMn LDH synthesis.
• Electrochemical characterization including turnover frequency (TOF) measurements.
• Anodic conditioning to investigate activity promotion.

Main Results:

• CoMn LDH nanoplates exhibited significantly higher TOF compared to Co/Mn oxides/hydroxides and IrO2.
• Anodic conditioning enhanced catalyst activity, likely through forming amorphous regions and reactive Co(IV) species.
• The catalyst demonstrated robust stability during prolonged electrolysis.

Conclusions:

• Ultrathin CoMn LDH nanoplates represent a highly active and stable OER catalyst.
• This earth-abundant material shows great promise for cost-effective solar fuel generation.
• Anodic conditioning is an effective strategy to further boost OER performance.