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Updated: Jun 25, 2026

Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
Published on: July 10, 2017
Direct Construction of Magnetic and Electrical Two-Dimensional Radical Covalent Organic Frameworks
Rajendra Prasad Paitandi1, Madhurima Giri2, Ryosuke Koyae2
1Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan. r.paitandi@gmail.com.
Abstract:
Radicals arranged in a two-dimensional (2D) hexagonal network can offer various exotic magnetic, electronic, and optical properties that find application in electronics/spintronics. However, direct synthesis remains challenging due to the scarcity of stable, symmetry-matched radical building blocks. Here, we report the bottom-up synthesis of hexagonal 2D radical covalent organic frameworks (RCOFs) with unpaired electrons at the nodes of the frameworks. A planar verdazyl radical amine (V-NH2) undergoes Schiff-base condensation with aldehydes to afford highly crystalline hexagonal RCOFs (VTPT and VPMT). The spin density was precisely controlled through the selection of building blocks with modulated spin-spin distances. The EPR and SQUID measurements confirmed a high spin concentration with antiferromagnetic interactions at low temperature, which is further tuned by interlayer interactions. Thin films of VTPT exhibited preferential in-plane orientation with enhanced photoconductivity, attributed to improved π-conjugation. These findings establish a direct route to RCOFs and underscore their potential as pseudo 1-dimensional antiferromagnetic materials.
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