Solid-State Fluorescence Sensor Based on SNW1 Nanoparticles for the Quantification of 2,4,6-Trinitrotoluene

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Science

Background:

• Accurate detection of 2,4,6-trinitrotoluene (TNT) is crucial for public safety, environmental monitoring, and health protection.
• Covalent organic frameworks (COFs) show promise for developing sensitive fluorescence-based sensors for explosives detection.

Purpose of the Study:

• To develop a novel, solid-state fluorescence probe for the detection of 2,4,6-trinitrotoluene (TNT).
• To establish a "Turn-off" sensor system utilizing a melamine-based COF for enhanced TNT sensing capabilities.

Main Methods:

• Fabrication of a novel melamine-based COF (SNW1) and its deposition onto a Fluorine-doped tin oxide (FTO) substrate via electrospray deposition, creating the SNW1@FTO sensor.
• Optimization of critical parameters including coating time, absorption, and desorption for sensor performance.
• Investigation of the fluorescence quenching mechanism upon TNT interaction, attributed to acceptor-donor interactions.

Main Results:

• The SNW1@FTO sensor demonstrated effective "Turn-off" detection of TNT through fluorescence quenching.
• The probe exhibited good selectivity and sensitivity for TNT detection within the concentration range of 5 to 700 µmol L⁻¹.
• Successful application of the sensor for quantifying TNT in real-world samples with satisfactory accuracy.

Conclusions:

• The developed SNW1@FTO probe represents a novel and effective solid-state sensor for TNT detection.
• The sensor's high sensitivity, selectivity, and applicability to real samples highlight its potential for practical security and environmental monitoring.
• This work advances the use of COF-based materials in developing advanced sensor technologies for hazardous substance detection.