Determination and identification of nitroaromatic explosives by a double-emitter sensor array.

Area of Science:

• Analytical Chemistry
• Materials Science
• Environmental Science

Background:

• Nitroaromatic explosives pose significant risks to human health, public safety, and the environment.
• Accurate and rapid detection of these compounds is critical for security and environmental monitoring.

Purpose of the Study:

• To develop a ratiometric sensor array for the detection and discrimination of common nitroaromatic explosives.
• To investigate the use of blue emissive carbon dots (BCDs) combined with yellow and red emissive cadmium telluride quantum dots (CdTe QDs) for sensing applications.

Main Methods:

• Fabrication of sensor elements (SE) using BCDs and CdTe QDs (SE-A and SE-B).
• Utilizing fluorescence quenching and spectral shifts of BCDs and QDs upon interaction with nitroaromatics.
• Developing a ratiometric approach for enhanced detection and discrimination.

Main Results:

• The sensor array successfully detected and discriminated between 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenol (TNP), and 2,4-dinitrotoluene (DNT).
• Nitroaromatics caused varying degrees of fluorescence quenching and spectral shifts in the BCDs and QDs.
• A low limit of quantification (5.0 μmol L⁻¹) was achieved for nitroaromatic detection in the concentration range of 5.0–200.0 μmol L⁻¹.
• The sensor array demonstrated effective detection of nitroaromatics in mixtures and complex environmental samples (soil and groundwater).

Conclusions:

• The developed double-emitter sensor array provides a sensitive and selective method for nitroaromatic explosive detection.
• This ratiometric sensing approach shows significant potential for real-world applications in security and environmental monitoring.
• The sensor's ability to function in complex media highlights its practical utility.