Pyrimidine-Functionalized Covalent Organic Framework and its Cobalt Complex as an Efficient Electrocatalyst for...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Covalent organic frameworks (COFs) offer tunable structures for catalytic applications.
• Nitrogen-rich heterocycles are effective coordinating ligands for metal ions.
• Efficient electrocatalysts for the oxygen evolution reaction (OER) are crucial for energy conversion technologies.

Purpose of the Study:

• To design and synthesize a pyrimidine-modified covalent organic framework (COF-Pyr).
• To develop a stable metal composite material (Co@COF-Pyr) for electrocatalysis.
• To evaluate the performance of Co@COF-Pyr for the oxygen evolution reaction (OER).

Main Methods:

• Synthesis of COF-Pyr via the Povarov reaction.
• Formation of the cobalt composite material (Co@COF-Pyr).
• Electrocatalytic testing in 1.0 M KOH for OER performance evaluation.

Main Results:

• Co@COF-Pyr exhibited a low overpotential of 450 mV at 10 mA cm⁻² for OER.
• The material possessed a high specific surface area (392 m² g⁻¹) and regular crystal structure.
• Achieved a turnover frequency of 0.1 s⁻¹ at 370 mV overpotential, outperforming many existing OER catalysts.

Conclusions:

• Pyrimidine-modified COFs are effective platforms for creating high-performance electrocatalysts.
• The nitrogen atoms in COF-Pyr provide excellent coordination sites for metal ions.
• This work presents a new strategy for designing nitrogen-containing heterocyclic functionalized COFs for electrocatalysis.