Bismuth Ferrite as an Electrocatalyst for the Electrochemical Nitrate Reduction

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Chemistry

Background:

• Electrochemical nitrate reduction is a promising sustainable method for ammonia (NH3) synthesis under mild conditions.
• Developing efficient catalysts for this complex eight-electron reaction remains a significant challenge.

Purpose of the Study:

• To investigate bismuth ferrite (BiFeO3) flakes as a catalyst for electrochemical ammonia synthesis via nitrate reduction.
• To evaluate the activity, Faradaic efficiency, and durability of BiFeO3 catalysts.

Main Methods:

• Synthesis of bismuth ferrite (BiFeO3) flakes with a distorted perovskite-type structure.
• Electrochemical testing of BiFeO3 catalysts for nitrate reduction.
• Analysis of catalyst phase transformation during the reaction.

Main Results:

• BiFeO3 flakes exhibited excellent catalytic activity for electrochemical NH3 synthesis.
• Achieved a maximum Faradaic efficiency of 96.85% and an NH3 yield of 90.45 mg h-1 mgcat-1 at -0.6 V vs. RHE.
• Observed rapid conversion of crystalline BiFeO3 to a stable amorphous phase during nitrate reduction, indicating good durability.

Conclusions:

• BiFeO3 is a highly effective electrocatalyst for sustainable ammonia synthesis from nitrate reduction.
• The in-situ phase transformation contributes to the catalyst's stability and performance.
• This work provides insights for designing advanced electrocatalysts for nitrogen-based energy conversion.