Surface Oxophilicity Driven ^*N Pathway Tuning for Selective Nitrate Electroreduction to Nitrogen

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Chemistry

Background:

• Nitrate pollution poses environmental risks.
• Electrochemical reduction of nitrate to nitrogen (N₂) is a sustainable solution.
• Current methods often rely on chlorine, causing secondary contamination.

Purpose of the Study:

• To develop a highly selective and efficient catalyst for electrochemical nitrate reduction to N₂.
• To investigate a surface-oxophilicity strategy to enhance N₂ selectivity.
• To suppress ammonia formation during nitrate reduction.

Main Methods:

• Developed PdSn metallene aerogels using a surface-oxophilicity strategy.
• Employed in situ characterization and theoretical analyses.
• Integrated the catalyst into a Zn-NO₃⁻ battery and a flow electrolyzer.

Main Results:

• Achieved ~97% nitrate-N conversion and ~99% N₂ selectivity.
• Demonstrated long-term stability (>600 h) and tolerance to varying nitrate concentrations.
• Sn doping enhanced intermediate adsorption and suppressed ammonia formation.

Conclusions:

• The PdSn catalyst effectively converts nitrate to N₂ with high selectivity and stability.
• The surface-oxophilicity strategy is crucial for enhancing catalytic performance.
• This approach offers a promising platform for sustainable nitrogen recycling and energy conversion.