| With the continuous improvement of living standards,environmental and health issues have attracted widespread attention in recent years.As a nitroaromatic compound,the explosive residues of 2,4,6-Trinitrotoluene?TNT?can cause serious damage to organisms and environment.Hence,it is necessary to analyze trace TNT residues in the environment of explosion site.Ascorbic acid?AA?is a vitamin that has a huge impact on human health,which cannot be synthesized by the body itself and needs to be supplemented from outside.When the content of AA is abnormal,it often leads to the emergence of some physical diseases.Therefore,rapid and accurate detection of AA can realize the early detection,early diagnosis and early treatment of some diseases.In recent years,the requirements of electrode modification material have been increasing in the field of electrochemical sensing.In order to meet the required sensitivity and detection limit requirements,it is necessary to modify metal nanomaterials to obtain metal nanocomposites.In this paper,metal nanocomposite materials electrochemical sensors were constructed,and its application in the determination of TNT and AA.The main point of this thesis are briefly summarized as follows:?1?The furfural film and copper nanoparticles were prepared by a one-step electrochemical polymerization method and a one-step electrochemical deposition method,respectively.and the sensor was used to realize the highly sensitive and selective detection of TNT.During the experiment,the influence of the number of polymerization cycles and the influence of the deposition potential and deposition time on the morphology and detection performance of the modified electrode were explored.The effects of scanning rate,enrichment time,enrichment potential and p H of the test solution on the electrochemical signal of TNT on the modified electrode also have been explored.Under the best electrode preparation conditions and detection conditions,The linear range of the modified electrode to TNT is 0.22 to 26.4?mol·L-1and the detection limit is 0.18?mol·L-1.In addition,the modified electrode also has good reproducibility,stability and anti-interference ability,and satisfactory results were obtained when the modified electrode was used for the detection of TNT in real water samples.?2?A 2-methylimidazole zinc salt?ZIF-8?film was deposited on the surface of the platinum nanoparticle?Pt NPs?modified glassy carbon electrode?GCE?by reduction electrochemical method to obtain ZIF-8/Pt NPs/GCE,and the sensor was used for electrochemical detection of AA.The deposition of Pt NPs on the surface of the glassy carbon electrode can direct the nucleation and growth of ZIF-8,and have a synergistic effect with the ZIF-8 membrane.The deposition of ZIF-8 film on the electrode surface can significantly increase the active electrode area,so that the electrochemical response of the modified electrode to AA is significantly improved.During the experiment,the effects of deposition current density and deposition time on the surface morphology of the modified electrode and the detection performance of the modified electrode in AA were investigated.The experiment also found that the addition of platinum nanoparticles plays an important role in ZIF-8 film deposition.In addition,we also explored the effects of scan rate and p H of the test solution on the electrochemical signal of AA on the modified electrode.Under the best electrode preparation conditions and detection conditions,the linear range is 10 to 2500?mol·L-1and the detection limit is 5.2?mol·L-1.In addition,the modified electrode has good anti-interference ability,reproducibility and stability,and satisfactory result rate were obtained in the detection process of real drugs. |
PDF Full Text Request