Pd NPs/MGO COOH based electrochemical sensor for detection of unsymmetrical dimethylhydrazine

Unsymmetrical dimethylhydrazine (UDMH) was used as hydrazine fuels in the aerospace field because of its high specific impulse and advantageous storage properties. In the development of the defense industry, large quantities of wastewater-containing UDMH, a carcinogenic chemical, are often released into the environment. In fact, accumulation of low concentrations of UDMH over a long period of time can also be hazardous to the human health and the environment. Therefore, rapid and accurate detection methods of UDMH at low concentrations are urgently needed in the defense industry sector in order to protect water resources and the environment. Herein, a carboxy-functional group ligand was constructed to act synergistically with metal nanoparticles for the detection of UDMH in wastewater. An in situ electrochemical deposition method was used to synthesize Pd NPs/monolayer carboxylated graphene oxide (MGOCOOH) which was employed, for the first time, as a high-efficient electrode to detect UDMH in aqueous medium. The experimental findings showed the linear range of Pd NPs/MGOCOOH electrode detection of UDMH ranging from 0.1 to 0.9 μg.L−1 and the limit of detection (LOD) was 0.012 μg.L−1 (S/N = 3). The Pd NPs/MGOCOOH electrode was employed for sensing of UDMH in water from the tap with good recovery rate. To define the possible structure of UDMH during detection process, Gaussian software was utilized to calculate the possible structure intermediates of UDMH at the B3LYP-D3BJ/def2tzvp level. Finally, the possible mechanisms are discussed. These findings show that the obtained Pd NPs/MGOCOOH composite electrode can serve as a prospective sensing composite for the detection of industrial contaminants in wastewater.