Downsizing Porphyrin Covalent Organic Framework Particles Using Protected Precursors for Electrocatalytic CO₂...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Covalent organic frameworks (COFs) are excellent electrocatalyst platforms due to their tunable structure, porosity, and stability.
• Porphyrin-based COFs show promise for CO2 reduction, but their large, uncontrolled particle sizes and aggregation limit performance.
• Controlling COF morphology is crucial for optimizing electrocatalytic efficiency.

Purpose of the Study:

• To develop a novel synthetic strategy for producing downsized COF catalyst particles.
• To investigate the impact of particle size on the electrocatalytic performance of COFs for CO2 reduction.
• To enhance the efficiency and CO production rate of COF-based electrocatalysts.

Main Methods:

• A new synthetic methodology using a tritylated amine as a protected porphyrin precursor for COF synthesis.
• In situ deprotection of the trityl group under standard COF synthesis conditions.
• Homogeneous nucleation and colloidal growth to achieve smaller COF particles with suppressed aggregation.

Main Results:

• The novel method yielded significantly smaller COF particles compared to conventional synthesis, attributed to reduced crystallite aggregation.
• Downsized COF catalysts demonstrated superior performance in electrochemical CO2 reduction, achieving higher CO production rates.
• The improved catalytic activity was linked to an increased contact area between the COF particles and conductive agents.

Conclusions:

• Particle size is a critical parameter influencing the performance of COF electrocatalysts.
• The developed synthetic approach offers an effective strategy for controlling COF particle size and enhancing CO2 reduction catalysis.
• This work paves the way for designing more efficient COF-based electrocatalysts by optimizing morphology.