Zhenting Zhao

Preparation and characterization of AuNPs/CNTs-ErGO electrochemical sensors for highly sensitive detection of hydrazine

A highly sensitive electrochemical sensor of hydrazine has been fabricated by Au nanoparticles (AuNPs) coating of carbon nanotubes-electrochemical reduced graphene oxide composite film (CNTs-ErGO) on glassy carbon electrode (GCE). Cyclic voltammetry and potential amperometry have been used to investigate the electrochemical properties of the fabricated sensors for hydrazine detection. The performances of the sensors were optimized by varying the CNTs to ErGO ratio and the quantity of Au nanoparticles. The results show that under optimal conditions, a sensitivity of 9.73μAμM(-1)cm(-2), a short response time of 3s, and a low detection limit of 0.065μM could be achieved with a linear concentration response range from 0.3μM to 319μM. The enhanced electrochemical performances could be attributed to the synergistic effect between AuNPs and CNTs-ErGO film and the outstanding catalytic effect of the Au nanoparticles. Finally, the sensor was successfully used to analyse the tap water, showing high potential for practical applications.

A highly sensitive electrochemical sensor based on Cu/Cu2O@carbon nanocomposite structures for hydrazine detection

We report a simple and large-scale fabrication of carbon-coated Cu/Cu2O nanocomposite materials (Cu/Cu2O@carbon) and their application as sensing materials for hydrazine detection in a neutral medium. The Cu/Cu2O@carbon nanocomposite structures were successfully synthesized using a facile, cost-effective calcination method. The morphology, crystalline structure, and composition of the prepared Cu/Cu2O@carbon were characterized by scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and high-resolution transmission electron microscopy. The hydrazine electrochemical sensor was fabricated by painting Cu/Cu2O@carbon on a glassy carbon electrode and immobilized using Nafion. By optimizing the Cu/Cu2O@carbon modified quantity and evaluating the performance using cyclic voltammetry and amperometry techniques, we demonstrated an optimal hydrazine electrochemical sensor with a high sensitivity of 2.37 μA μM−1 cm−2, an excellent linear concentration range of 0.25 μM to 800 μM, and a low detection limit of 0.022 μM.