One-pot synthesis of high-density Pd nanoflowers decorated 3D carbon nanotube-graphene network modified on printed electrode as portable electrochemical sensing platform for sensitive detection of nitroaromatic explosives

The maintenance of public security from warfare agents stimulates the growing demand in the development of portable sensors for explosives detection. In this work, a portable electrochemical sensor integrated with a nanohybrid modified printed electrode and miniaturized electrochemical readout, has been established for highly sensitive and rapid in situ detection of explosives. For the preparation of the modified printed electrode, the active electrode material Pd nanoflowers (PdNFs) decorated carbon nanotubes (CNTs)-graphene nanosheets (GNSs) nanocomposite (PdNFs-CNTs-GNSs) has been synthesized by a facile and effective one-pot chemical reduction and assembly from a mixture of their precursors, this enables the formation of highly dense and well dispersed PdNFs on 3D porous CNTs-GNSs network, which effectively increases the electrode active surface area and improves the electrocatalytic activity. For electrochemical detection of a series of explosive nitroaromatic compounds such as p-nitrophenol (4-NP), dinitrobenzene (DNB), 1-choloro-2,4-dinitrobenzene (Cl-DNB), 2,4-dinitrotoluene (DNT), trinitrobenzene (TNB) and trinitrotoluene (TNT), the developed portable electrochemical sensor with PdNFs-CNTs-GNSs modified printed electrode shows attractive analytical features such as good sensitivity, widely operational linear range for determination, low detection limit and high selectivity, and can be used for the sensitive and accurate measurement of nitroaromatic compounds in environmental samples.