Construction And Application Of Hydrazine Electrochemical Sensor Based On Palladium-Carbon Based Nanocomposites

Hydrazine play an indispensable role in industrial production and agricultural development.However,human contact and absorption of hydrazine can harm human health.Therefore,the development of hydrazine rapid and accurate detection method is particularly important.Among the many techniques for detecting hydrazine,electrochemical detection is receiving more and more attention and research because of its fastness,high sensitivity,good selectivity,simplicity and low cost.In order to improve the performance of electrochemical detection of hydrazine,nanomaterials have been used in the preparation of hydrazine electrochemical sensors.However,the current hydrazine electrochemical sensors based on nanomaterials still have problems such as high catalytic potential,low sensitivity and complicated materials synthesis,which greatly affects the development of hydrazine electrochemical sensors.In this paper,novel nanomaterials were prepared by new synthetic methods to improve the performance of hydrazine electrochemical sensors and simplify the preparation process of nanomaterials,which provided an effective method for the determination of hydrazine with great potential for practical application in the future.（1）Two kinds of novel nanomaterials were prepared in this thesis:Palladium nanoparticles loaded on cobalt nanoparticles wrapped in nitrogen-doped carbon nanotubes（Pd/Co-NCNTs）nanocomposites were successfully obtained by pyrolysis at high temperature.Laser scribed graphitic carbon nanosheets loading palladium nanoparticles（Pd/LSGCNs）nanocomposites were successfully prepared by the laser-scribed process preparing laser scribed graphitic carbon nanosheets（LSGCNs）and then Pd NPs electrodeposited on the conductive LSGCNs.In order to explore the composition and microstructure of nanomaterials,we use SEM,TEM,XRD,XPS,Raman and other characterization methods for analysis and verification.（2）Pd/Co-NCNTs/GCE was prepared by using Pd/Co-NCNTs nanocomposites,and then the electrochemical behavior of hydrazine at the electrode was investigated.Due to the synergism of Pd and Co-NCNTs,Pd/Co-NCNTs/GCE has a good catalytic effect for hydrazine oxidation.The prepared electrochemical sensor has a linear range of 0.05-406μmol?L^-1 for hydrazine and a limit of detection（S/N=3）of 0.007μmol?L^-1.In addition,the prepared electrochemical sensors enable the detection of hydrazine in tap water and lake samples.（3）The Pd/LSGCNs nanocomposites were prepared by laser scribing and modified on glassy carbon electrode（GCE）.The modified electrode had better catalytic effect on the electrochemical oxidation of hydrazine.After optimization of the experimental conditions,the sensor can detect hydrazine sensitively with a linear range of 0.12-888μmol?L^-1 and a detection limit（S/N=3）of 0.01μmol?L^-1.Due to the simple and fast synthesis method,the nanomaterials are expected to be widely used in the detection of hydrazine in the environment.