Selective Urea Electrosynthesis from CO₂ and Nitrate on Spin-Polarized Atomically Ordered PdCuCo

Area of Science:

• Catalysis
• Electrochemistry
• Materials Science

Background:

• Electrocatalytic conversion of nitrate (NO3-) and carbon dioxide (CO2) offers a sustainable route for urea production.
• Low efficiency in carbon-nitrogen (C-N) coupling and competing ammonia formation limit current urea electrosynthesis.
• Developing advanced catalysts is crucial for enhancing urea selectivity and yield.

Purpose of the Study:

• To develop an efficient electrocatalyst for urea synthesis from NO3- and CO2.
• To investigate the role of spin-polarized cobalt doping in promoting C-N coupling for urea production.
• To understand the reaction mechanism and optimize catalyst performance.

Main Methods:

• Synthesis of a spin-polarized cobalt-doped, atomically ordered PdCu intermetallic compound (PdCuCo).
• Electrochemical testing of PdCuCo for urea electrosynthesis from NO3- and CO2.
• Analysis of reaction pathways and intermediate adsorption using theoretical and experimental approaches.

Main Results:

• The PdCuCo catalyst achieved a high Faradaic efficiency of 81% for urea electrosynthesis.
• An outstanding urea yield of 227 mmol gcat.-1 h-1 was recorded.
• The catalyst demonstrated excellent electrochemical stability, operating for over 260 hours.
• Spin-polarized Co sites were shown to promote specific *NO intermediate hydrogenation, favoring urea formation over ammonia.

Conclusions:

• The developed PdCuCo electrocatalyst significantly enhances urea electrosynthesis efficiency and selectivity.
• Designing spin-polarized catalytic sites is a promising strategy for improving C-N coupling reactions.
• This work paves the way for sustainable urea production and carbon footprint reduction.