Modulating the Active Hydrogen Adsorption on Fe─N Interface for Boosted Electrocatalytic Nitrate Reduction with...

Area of Science:

• Materials Science
• Electrochemistry
• Environmental Science

Background:

• Electrocatalytic nitrate reduction to nitrogen (N2) offers a sustainable N-cycle management strategy.
• Challenges include poor catalyst durability and competing hydrogen evolution reactions.
• Interface-chemistry engineering is key to enhancing catalyst performance.

Purpose of the Study:

• To synthesize and evaluate a nitrogen-doped carbon-coated rice-like iron nitride (RL-Fe2N@NC) electrocatalyst.
• To investigate the catalyst's activity, selectivity, and stability for nitrate reduction.
• To elucidate the reaction mechanism through in situ tests and theoretical calculations.

Main Methods:

• Synthesis of nitrogen-doped carbon-coated rice-like iron nitride (RL-Fe2N@NC).
• Electrocatalytic performance testing for nitrate reduction (activity, selectivity, stability).
• In situ spectroscopic tests and theoretical calculations for mechanistic studies.

Main Results:

• RL-Fe2N@NC achieved high N2 selectivity (≈96%) and nitrate conversion (≈86%).
• Mechanistic studies revealed synergistic effects of iron nitride hydrogenation and nitrate enrichment.
• The catalyst demonstrated excellent stability over 40 cycles.

Conclusions:

• The RL-Fe2N@NC electrocatalyst shows significant promise for efficient and stable nitrate reduction to nitrogen.
• Interface engineering of Fe-based composites is a viable strategy for N-cycle management.
• This work contributes to achieving nitrogen neutrality through advanced electrocatalysis.