Wafer-Scale Synthesis of Molecularly Engineered 2D Covalent Organic Framework Films for Highly-Sensitive and
Liangyu Dong1, Can Wang1, Jiawen Liu1
1State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun, China.
Advanced Materials (Deerfield Beach, Fla.)
|February 27, 2026
Summary
Rational molecular engineering of 2D COF films enables highly sensitive and fast humidity sensors. These advanced sensors demonstrate potential for real-time wearable respiratory monitoring and disease detection.
Area of Science:
- Materials Science
- Nanotechnology
- Chemical Engineering
Background:
- Covalent organic frameworks (COFs) show promise for humidity sensing but lack controlled structure-property relationships.
- Uncontrolled molecular design and nanoscale architecture limit practical COF sensor applications.
Purpose of the Study:
- To rationally engineer ultrathin 2D imine-linked COF films for exceptional humidity sensing.
- To establish precise control over electronic band structure, porosity, and hygroscopicity.
- To unveil structure-property correlations for high-performance COF sensors.
Main Methods:
- Wafer-scale, ultrathin 2D imine-linked COF films synthesized via interfacial polymerization.
- Incorporation of triazine and multi-hydroxyl groups into the COF structure (COFTPT-THTA).
- Characterization of electronic band structure, nanoscale porosity, and hygroscopicity.
Main Results:
- COFTPT-THTA based sensor achieved high sensitivity (66,124%/%RH), fast response/recovery (0.12/0.40 s), and minimal hysteresis (1.0% RH).
- Synergistic effects from high structural polarity, hydrophilicity, and confined pores enhance sensing performance.
- Nanometer-scale thickness and ultrasmooth surface improved charge transport and water adsorption kinetics.
Conclusions:
- A fundamental molecular engineering paradigm for 2D COF film sensors was established.
- Precise control over COF properties enables high-performance humidity sensing.
- Demonstrated potential for wearable sensors in real-time respiratory monitoring and pathological pattern detection.
