A two-dimensional MXene-supported metal-organic framework for highly selective ambient electrocatalytic nitrogen...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Ammonia synthesis is vital for human activities, with electrochemical methods offering a green alternative.
• Improving catalytic activity and selectivity is key for efficient electrochemical ammonia synthesis.
• Metal-organic frameworks (MOFs) and MXenes show promise as catalyst supports due to their unique properties.

Purpose of the Study:

• To develop a novel composite catalyst for electrochemical ammonia synthesis.
• To investigate the synergistic effects of ZIF-67 and Ti3C2 MXene for the nitrogen reduction reaction (NRR).
• To evaluate the catalytic performance of the ZIF-67@Ti3C2 composite in terms of ammonia yield and Faraday efficiency.

Main Methods:

• In situ growth of Co-based zeolitic imidazolate framework-67 (ZIF-67) on Ti3C2 MXene.
• Electrochemical synthesis of ammonia from nitrogen and water.
• Characterization of the ZIF-67@Ti3C2 composite catalyst.
• Performance evaluation using ammonia yield and Faraday efficiency measurements.

Main Results:

• The ZIF-67@Ti3C2 composite catalyst demonstrated a high NH3 yield of 6.52 μmol h-1 cm-2.
• The composite significantly outperformed individual Ti3C2 and ZIF-67 catalysts.
• A good Faraday efficiency of 20.2% was achieved at -0.4 V vs. the reversible hydrogen electrode.

Conclusions:

• The ZIF-67@Ti3C2 composite is an effective electrocatalyst for ammonia synthesis.
• The combination of MOF porosity and MXene conductivity enhances NRR performance.
• This work expands the application of MXenes in electrocatalysis and offers insights for designing high-performance NRR electrocatalysts.