Interface engineering in a Cu-CoO heterostructure for high-efficiency electrocatalytic nitrate reduction to ammonia

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Nitrate (NO3-) contamination in water poses environmental risks.
• Efficient electrochemical reduction of nitrate to ammonia (NH3) is a sustainable solution.
• Developing advanced catalysts is crucial for enhancing this conversion process.

Purpose of the Study:

• To synthesize and characterize a novel Cu-CoO@CNT heterostructure catalyst.
• To evaluate the electrocatalytic performance of the synthesized catalyst for NO3- to NH3 conversion.
• To understand the mechanism behind the catalyst's enhanced activity.

Main Methods:

• Synthesis of Cu-CoO@CNT heterostructure catalyst.
• Electrochemical characterization using techniques like linear sweep voltammetry and chronoamperometry.
• Analysis of ammonia yield and Faradaic efficiency (FE).

Main Results:

• The Cu-CoO@CNT catalyst demonstrated superior electrocatalytic activity.
• Achieved a maximum NH3-Faradaic efficiency of 98.1 ± 1.5% at -0.6 V vs. RHE.
• Identified electron transfer-induced structural transition stabilizing active Cu+2 valence state.

Conclusions:

• The Cu-CoO@CNT heterostructure is a highly effective catalyst for electrochemical nitrate-to-ammonia conversion.
• The catalyst's performance is attributed to the stabilization of active copper species.
• This work offers a promising pathway for sustainable ammonia production and nitrate remediation.