Boron-Modified Ni-Cu Heterostructure Electrocatalyst for Nitrate Reduction to Ammonia

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Engineering

Background:

• Electrochemical nitrate reduction is a promising dual strategy for sustainable ammonia production and nitrate-contaminated water remediation.
• Development of highly active, selective, and stable electrocatalysts is crucial for efficient nitrate reduction reaction (NO3RR).

Purpose of the Study:

• To develop and investigate a boron-modified nickel-copper heterostructure catalyst for the electrochemical nitrate reduction reaction.
• To assess the catalyst's performance in terms of ammonia yield, selectivity, and durability.
• To elucidate the mechanistic role of boron doping in enhancing catalytic activity.

Main Methods:

• Synthesis of a boron-modified nickel-copper heterostructure catalyst (B-Ni2(CO3)(OH)2/Cu(OH)2/CF).
• Electrochemical characterization of the catalyst for nitrate reduction reaction (NO3RR) performance evaluation.
• Mechanistic studies to understand the effect of boron doping on catalyst properties and reaction pathways.

Main Results:

• The B-Ni2(CO3)(OH)2/Cu(OH)2/CF catalyst achieved a high ammonia yield of 6.8 mg h−1 cm−2 with 92.0% Faradaic efficiency at -0.7 V (vs RHE).
• The catalyst exhibited excellent durability during extended electrochemical operation.
• Boron doping was found to induce surface BOx species and modulate the electronic structure of Ni sites, enhancing nitrate activation and hydrogenation kinetics.

Conclusions:

• Boron doping is an effective strategy for designing advanced electrocatalysts for efficient nitrate-to-ammonia conversion.
• The developed catalyst offers a sustainable pathway for simultaneous water detoxification and valuable ammonia recovery.
• This research provides insights into catalyst design for electrochemical applications in environmental remediation and chemical synthesis.