Regulating the Electron Localization of Metallic Bismuth for Boosting CO₂ Electroreduction

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrochemical reduction of carbon dioxide (CO2) to formate is a promising route for CO2 utilization.
• Achieving high selectivity and activity in CO2 electroreduction remains a significant challenge.

Purpose of the Study:

• To enhance the selectivity and activity of bismuth-based electrocatalysts for CO2 reduction to formate.
• To investigate the mechanistic role of boron doping in modifying bismuth's electronic structure and catalytic performance.

Main Methods:

• Experimental synthesis and characterization of boron-doped bismuth (B-Bi) electrocatalysts.
• Electrochemical measurements including cyclic voltammetry and chronoamperometry.
• Density functional theory (DFT) calculations for mechanistic insights.

Main Results:

• Boron doping creates positive valence sites on bismuth, significantly boosting CO2 conversion to formate.
• B-Bi catalysts exhibit high activity and selectivity over a wide potential window.
• DFT calculations reveal that boron doping alters proton participation in rate-determining steps for both CO2 reduction and hydrogen evolution.

Conclusions:

• Boron doping is an effective strategy for designing highly active and selective electrocatalysts for CO2 conversion.
• The study provides detailed mechanistic understanding of boron's role at the atomic level.
• This work offers a pathway for rational design of efficient electrocatalysts for sustainable CO2 utilization.