Porous Azatruxene Covalent Organic Frameworks for Anion Insertion in Battery Cells.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Covalent organic frameworks (COFs) with redox-active groups are emerging as key materials for next-generation batteries.
• There is a limited number of p-type COFs reported for charge storage, and even fewer for multivalent ion batteries.

Purpose of the Study:

• To synthesize and characterize a novel p-type, porous, crystalline azatruxene-based COF.
• To evaluate the synthesized COF as a positive electrode material in both lithium (Li)- and magnesium (Mg)-based batteries.

Main Methods:

• Synthesis of a highly porous and crystalline azatruxene-based COF.
• Fabrication of COF/carbon nanotube (CNT) composite electrodes.
• Electrochemical testing in Li-based half cells and Mg-based battery configurations.

Main Results:

• The COF/CNT electrode in Li-based half cells achieved a discharge potential of 3.9 V with capacities up to 70 mAh g^-1 at 2 C.
• In Mg batteries, the COF electrode exhibited an average discharge voltage of 2.9 V.
• Excellent cycling stability was observed in Mg batteries, with 84% capacity retention over 1000 cycles even at a 5 C rate.

Conclusions:

• The synthesized azatruxene-based COF is a viable p-type electrode material for advanced energy storage applications.
• The material shows potential for use in both lithium and multivalent ion batteries, particularly magnesium batteries, offering high voltage and stability.