High-Performance N₂-to-NH₃ Conversion Electrocatalyzed by Mo₂C Nanorod.

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• The Haber-Bosch process, dominant for ammonia (NH3) synthesis, is highly energy-intensive and a significant source of CO2 emissions.
• Electrochemical nitrogen reduction reaction (NRR) offers a sustainable, carbon-free alternative for NH3 production.
• Development of efficient and stable electrocatalysts is crucial for advancing NRR technology.

Purpose of the Study:

• To investigate molybdenum carbide (Mo2C) nanorods as a novel electrocatalyst for the artificial nitrogen reduction reaction (NRR).
• To evaluate the performance, durability, and selectivity of Mo2C nanorods for NH3 synthesis under ambient conditions.
• To elucidate the catalytic mechanism of Mo2C in NRR using density functional theory (DFT) calculations.

Main Methods:

• Synthesis of Mo2C nanorods.
• Electrochemical characterization of Mo2C nanorods for NRR.
• Ammonia yield and Faradaic efficiency measurements.
• Density functional theory (DFT) calculations for mechanistic studies.

Main Results:

• Mo2C nanorods demonstrated excellent electrocatalytic activity and stability for NRR.
• Achieved a high Faradaic efficiency of 8.13% and an NH3 yield of 95.1 μg h-1 mg-1 cat at -0.3 V in 0.1 M HCl.
• The catalyst exhibited strong durability and acceptable selectivity for ammonia production.
• DFT calculations provided insights into the catalytic mechanism.

Conclusions:

• Mo2C nanorods are highly effective electrocatalysts for artificial N2 fixation to NH3.
• This carbon-free NRR process using Mo2C nanorods shows significant potential for sustainable ammonia synthesis.
• The findings surpass the performance of many previously reported NRR electrocatalysts.