Engineering Water Molecules Activation Center on Multisite Electrocatalysts for Enhanced CO₂ Methanation

Area of Science:

• Electrochemistry
• Catalysis
• Materials Science

Background:

• Electrolytic reduction of carbon dioxide (CO2) to methane (CH4) is key for renewable energy storage.
• Slow water dissociation kinetics hinder proton supply, limiting CO2 methanation efficiency.
• The role of water in electrolytes is often overlooked in CO2 conversion.

Purpose of the Study:

• To develop a novel tandem catalyst for efficient CO2 to CH4 conversion.
• To investigate the role of water dissociation in the methanation process.
• To enhance selectivity and activity in multi-electron transfer reactions.

Main Methods:

• Synthesis of a novel tandem catalyst: Ir single-atom (Ir1)-doped hybrid Cu3N/Cu2O multisite.
• Experimental characterization of catalyst performance.
• Theoretical calculations to elucidate reaction mechanisms.

Main Results:

• The Ir1 facilitates water dissociation, supplying protons for CO2 reduction.
• The catalyst promotes the *CO protonation pathway toward *CHO.
• Achieved 75% Faradaic efficiency for CH4 production at 320 mA cm-2 in a flow cell.

Conclusions:

• The Ir1-doped Cu3N/Cu2O catalyst offers an efficient pathway for CO2 methanation.
• Facilitating water dissociation is crucial for high-performance CO2 reduction.
• This work presents a strategy for designing advanced multisite catalysts for energy applications.