Electrochemical detection of TNT using CdS nanoparticles via cyclic voltammetry and amperometry

Abstract

In this work, we report the sensing of explosive 2, 4, 6-trinitrotoluene (TNT) using PEG-coated cadmium sulfide (P–CdS) nanoparticles (NPs). The P–CdS NPs were synthesized using microwave assisted method. The synthesized NPs were found to be excellent electron mediator between TNT and gold electrode. The modified gold electrode with P–CdS NPs was used as working electrode. Cyclic voltammetry and amperometry techniques were employed for electrochemical sensing. The fabricated sensor showed the sensitivity of 47.8 ​μA ​cm−2 ​μM−1 and the limit of detection as 1.045 ​nM, which is far less than 88 ​nM allowed by US Environmental Protection Agency (EPA). The method has been found to be selective for TNT, as addition of nitrobenzene and 2, 4-dinitrotoluene has given nearly no response in amperometric method. The method has been applied to spiked water samples. Thus, the proposed method can be successfully employed in detection of TNT in real samples.

Keywords

• CdS NPs
• 2
• 4
• 6-Trinitrotoluene (TNT)
• Electrochemical sensor
• Cyclic voltammetry