Ultrathin Bismuth Nanosheets as a Highly Efficient CO₂ Reduction Electrocatalyst

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrochemical reduction of carbon dioxide (CO2) is crucial for sustainable energy solutions.
• Developing efficient catalysts for CO2 conversion remains a significant challenge.

Purpose of the Study:

• To synthesize and characterize ultrathin bismuth nanosheets for CO2 electroreduction.
• To investigate the catalytic performance of bismuth nanosheets in converting CO2 to formate.

Main Methods:

• Electrochemical synthesis of bismuth nanosheets from Bi3+.
• Electrochemical reduction of CO2 in aqueous solution.
• Characterization using techniques like DFT calculations.

Main Results:

• Bismuth nanosheets (approx. 10 nm thick) were successfully prepared.
• Faradaic efficiency for formate production exceeded 90% within -0.9 to -1.2 V vs. RHE.
• Bismuth nanosheets showed enhanced current density and selectivity for formate compared to bulk bismuth.
• DFT calculations revealed higher density of states at the Fermi level for nanosheets, favoring CO2 reduction.

Conclusions:

• Ultrathin bismuth nanosheets are highly efficient electrocatalysts for CO2 reduction to formate.
• The unique properties of nanosheets, including high surface area and electronic structure, enhance catalytic activity.
• Bismuth nanosheets demonstrate excellent selectivity and stability for formate generation.