High-performance electrocatalyst based on polyazine derived mesoporous nitrogen-doped carbon for oxygen reduction...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Metal-free electrocatalysts are crucial for renewable energy conversion.
• Nitrogen-doped porous carbons offer promising catalytic properties.
• Developing efficient and sustainable synthesis methods is essential.

Purpose of the Study:

• To develop a convenient and eco-friendly method for synthesizing nitrogen-doped mesoporous carbon (NMC).
• To investigate the structure-activity relationship of NMCs for oxygen reduction reactions (ORR).
• To evaluate the electrocatalytic performance and stability of NMCs as metal-free catalysts.

Main Methods:

• Fabrication of NMC using Pluronic F127 micelles as a template and polyazine as a precursor.
• Characterization of synthesized NMCs using BET (Brunauer-Emmett-Teller) and XPS (X-ray Photoelectron Spectroscopy).
• Electrochemical evaluation of NMC materials for ORR activity and stability.

Main Results:

• Spherical NMCs with high surface area (up to 1174 m² g⁻¹) and simultaneous nitrogen (2.9-19 at%) and oxygen (4.9-7.4 at%) doping were successfully synthesized.
• A direct correlation between ORR activity and pyridinic-nitrogen content was identified.
• NMC-700 exhibited the highest ORR electrocatalytic activity and excellent long-term stability, comparable to commercial Pt/C catalysts.

Conclusions:

• The developed method provides an efficient route to synthesize high-performance NMCs.
• Pyridinic-nitrogen is a key active site for ORR in these materials.
• NMCs are promising alternatives to platinum-based catalysts for energy conversion applications.