Realizing efficient ammonia electrosynthesis enabled by metal-organic framework-derived CuCo-LDH

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Chemistry

Background:

• Nitrate pollution is a significant environmental concern.
• Ammonia synthesis is crucial for agriculture and industry.
• Simultaneous wastewater treatment and ammonia production is highly desirable.

Purpose of the Study:

• To develop an efficient electrocatalyst for nitrate reduction to ammonia.
• To investigate the mechanism of nitrate reduction using bimetallic hydroxides.
• To integrate the process for practical ammonia production and wastewater remediation.

Main Methods:

• Synthesis of CuCo layered bimetallic hydroxides using ZIF-67 as a template.
• Electrocatalytic reduction of nitrate under optimized conditions.
• Characterization of the catalyst's structure and performance.
• Integration with an electrolysis-absorption unit for ammonia recovery.

Main Results:

• Achieved an ammonia yield of 7.27 mg h^-1 cm^-2.
• Obtained a high Faraday efficiency of 86.2% for ammonia production.
• Demonstrated stable operation for 120 hours.
• Successfully converted nitrate to high-purity ammonium sulfate.

Conclusions:

• CuCo layered bimetallic hydroxides are effective electrocatalysts for nitrate reduction to ammonia.
• The developed system offers a sustainable strategy for wastewater treatment and ammonia valorization.
• Integration of electrolysis and absorption provides a pathway for high-purity ammonia production.