Low Temperature Complexation Approach for Immobilization of Single Copper Atom Catalyst in Stacked Polytriazine for...

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• Synthesis of single-atom catalysts (SACs) often requires high temperatures and long reaction times.
• Graphitic carbon nitride (g-C3N4) is a promising matrix for SACs, but stabilizing metal atoms within it presents challenges.
• Existing methods for embedding SACs in g-C3N4 are energy-intensive and time-consuming.

Purpose of the Study:

• To develop a facile, low-temperature complexation approach for synthesizing single-atom catalysts (SACs) on a stacked polytriazine matrix (g-C3N4).
• To investigate the role of copper ion complexation in stabilizing single metal atoms within the g-C3N4 framework.
• To evaluate the catalytic performance of the synthesized copper SAC for click cycloaddition reactions.

Main Methods:

• Microwave-assisted synthesis at 140 °C for 30 minutes.
• Complexation of Cu2+/Cu+ ions with nitrogen atoms in the polytriazine structure.
• Characterization of the resulting SAC using surface area analysis (BET) and metal loading determination.

Main Results:

• Achieved a copper single-atom catalyst (SAC) with high metal loading (up to 3.5 wt.%) on g-C3N4.
• The complexation mechanism involving Cu+ and Cu2+ ions was elucidated, facilitating layer stacking and stabilization.
• The SAC exhibited a high surface area (330 m2 g-1) and specific pore size distribution.
• Demonstrated excellent catalytic activity (TOF of 120 h-1) for base-free click cycloaddition reactions with broad substrate scope and reusability over seven cycles without leaching.

Conclusions:

• The developed low-temperature complexation method offers an efficient and rapid alternative for synthesizing highly stable and active SACs on g-C3N4.
• The synthesized copper SAC is a promising catalyst for triazole synthesis via click chemistry.
• The findings provide insights into the stabilization mechanisms of metal atoms within g-C3N4 matrices.