Electrochemical Detection Of Heavyy Metal Ions By Oxygen Vacancy ZnO

At present,the pollution of heavy metals to the environment is a global problem.Therefore,it is important to develop effective detection techniques to determine the levels of heavy metal contamination in various media.These heavy metal ions are non-biodegradable and harm people’s health.Therefore,we urgently need a method to detect heavy metals.Very fast,sensitive and accurate tracking of heavy metal ions in the environment,food samples and drinking water is required.There are many conventional methods for detecting trace metals at lower concentrations.However,these technologies also have some limitations,such as high instrument cost,complex sample preparation,and the need for professionals to limit the detection and preconcentration of single components,making them unsuitable for real-time online detection and continuous monitoring.In addition,due to the large size of the equipment,it cannot be used for on-site testing.In contrast,electrochemical techniques are powerful sensing tools for the detection of heavy metal ions.The technology has the advantages of accuracy,simplicity,low cost,remarkable sensitivity,multiple detection effectiveness and field detection ability.It can effectively detect the heavy metal ions in our life.This paper compared the materials before plasma treatment to explore the application and influence of oxygen vacancy in electrochemical detection.Finding gaps in the direction of detection of heavy metals would substantially improve the material itself.The work of this paper is as follows:First,the flower-like ZnO nanomaterials were successfully prepared by constant temperature in water crucible,and rich oxygen vacancies were created by plasma treatment.Then,XPS,ESR and Raman were used to fully demonstrate the existence of oxygen vacancies.Raw materials and plasma-treated materials are then coated on the working electrode to form a three-electrode system for a series of electrochemical tests.It was found that the presence of oxygen vacancy could greatly improve the detection sensitivity of these three heavy metal ions.Also in the anti-interference experiment of materials,a conclusion was obtained:the addition of Cu(Ⅱ)to the vacancy flower-like zinc oxide in the detection of heavy metals can enhance the detection effect of Hg(Ⅱ),but the interference to Cu(Ⅱ)is very limited if Hg(Ⅱ)is added.In the experiment of conductivity and stability,we also found that the existence of oxygen vacancy can improve the stability and conductivity of the material to some extent.We also analyzed the actual water samples of these two materials and tested them with real wastewater,and the experimental results proved that the vacancy flower-like ZnO had a good application in the electrochemical analysis of heavy metal ions in the actual water samples.Secondly,the sheet ZnO nanomaterials were synthesized by hydrothermal method and rich oxygen vacancy was created by plasma treatment.Then,the existence of oxygen vacancy was fully demonstrated by XPS and ESR.After optimizing the experimental conditions,the electrochemical experiments with these two materials were continued.In the experiment,we can see that the vacancy type porous flake zinc oxide has a high detection sensitivity,which can be attributed to the presence of oxygen vacancy.Later,we also carried out a series of experiments on electrochemical detection with this comparative experimental method.By comparing the experimental results of the two materials,we also draw the conclusion that oxygen vacancy can improve the material’s own performance and detection performance.Finally,as in the first work,the actual water sample was tested and the heavy metal was detected in the actual wastewater.The results proved that the electrochemical analysis of heavy metal ions in the actual water sample also had a good application.