Related Experiment Video
Updated: May 15, 2026
08:42
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
Geometry-Identical Welding Unlocks Isoelectronic Engineering of Conductive Covalent Organic Frameworks.
Wenchang Chen1, Chao Yang1, Junqiang Jiao1
1State Key Laboratory of Precision and Intelligent Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 14, 2026
Summary
Researchers developed novel conductive covalent organic frameworks (COFs) using nickel phthalocyanine (NiPc) building blocks. These materials exhibit tunable electrical properties and can differentiate between nitrogen oxides (NO and NO2) in chemiresistive sensors.
Area of Science:
- Materials Science
- Nanotechnology
- Organic Electronics
Background:
- Developing advanced materials with tunable electrical properties is crucial for next-generation electronic devices.
- Covalent Organic Frameworks (COFs) offer a versatile platform for designing functional porous materials.
Purpose of the Study:
- To engineer novel conductive covalent organic frameworks (COFs) based on nickel phthalocyanine (NiPc) units.
- To investigate the impact of subtle structural modifications on the electrical conductivity and sensing capabilities of these COFs.
- To demonstrate the potential of these COFs in discriminating between different gaseous species.
Main Methods:
- Synthesis of two isoelectronic NiPc-based COFs using aromatic nucleophilic substitution.
- Characterization of the COFs' crystallinity, structure, and electrical conductivity.
- Incorporation of iodine to enhance conductivity.
- Fabrication and testing of chemiresistive sensors using the synthesized COFs.
Main Results:
- Two isoelectronic COFs with distinct conductivities (6 × 10⁻⁴ S cm⁻¹ vs. 7 × 10⁻⁶ S cm⁻¹) were successfully synthesized.
- Iodine doping significantly enhanced conductivity by 300% and 500%.
- The COFs demonstrated discriminated electronic responses to NO and NO₂, enabling selective detection.
Conclusions:
- Geometrically controlled assembly of NiPc units leads to high-quality COFs with tunable electronic properties.
- Subtle structural differences in COFs can profoundly impact their conductivity.
- These NiPc-based COFs show promise as selective and sensitive materials for gas sensing applications.
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