Electrochemical Detection Of Toxic And Hazardous Substances In Daily Necessities By Composite Nanomaterials Based On Carbon Black

The 21 st century is the information age,people's social activities mainly rely on the development of information resources and access,transmission and processing.Sensors are as a window of perception,access and detection of information,so the status of scientific research is very important.Electrochemical method has become a research hotspot because of its advantages such as simple instrument,fast analysis speed,high sensitivity and good stability.It has been widely used in chemical,pharmaceutical,biological and environmental protection fields.Nano-size objects or material having 1-100 nm nanostructures collectively referred to as nano-materials.Nano-materials with excellent physical and chemical property,are widely used in a number of areas,such as electrochemistry,colloidal chemistry,solid chemistry,coordination chemistry,chemical kinetics and so on.It has brought new opportunities and challenges for chemical research.In a variety of nano-materials,carbon nanomaterials have unique structure,which have excellent mechanical properties,electromagnetic properties,optical properties,and thermal properties.Carbon black is three-dimensional carbon material.Compared with other carbon materials,it has catalytic performance and better conductivity,which the cost is more affordable.Therefore,it has broader application prospects in the field of electrochemical research.In nano-materials,metal nanoparticles can be combined with a variety of biological macromolecules due to the high electron density,dielectric properties and catalytic role,and does not affect its biological activity,causing the interest of researchers;metal nanoparticles have large surface area,high free energy,the modified electrode,the electrode sensitivity and can be significantly increased.The introduction of metal nanoparticles into the modified electrode can achieve the catalytic and rapid detection of certain substances.The cavity structure inside the dendritic molecule gives it a unique property with a large number of amino functional groups on its surface.The nanomaterials prepared with dendrimers as templates are not only stable but also capable of maintaining the catalytic performance of nanoparticles.Chitosan as a natural polymer,has excellent biodegradability,biocompatibility,non-toxic and other excellent physical and chemical properties and biological properties and widely used in many fields.The work of this paper is devoted to the preparation of carbon black nanoparticles and their composites for electrochemical applications.The maincontents are divided into three parts:First,preparation of Au NPs/CB NPs GCE and its application for measurement of PPDIn this work,nanocomposite material as modifier of Au NPs/CB NPs/GCE,we construct a new modified method for electrochemical detection of PPD.The experimental results show that the modified Au NPs/CBNPs/GCE can significantly enhance the oxidation peak current of PPD by cyclic voltammetry,AC impedance method,square wave voltammetry and so on.The method is rapid,simple,sensitive.The detection range of PPD was 4 ?M ~ 10 ?M and 10 ?M ~ 100 ?M,and the detection limit was 1.1 ?M(S / N = 3).The electrochemical sensor to detect PPD in hair dyes also achieved good results,which has good prospects.Second,the preparation of modified PAMAM/CB NPs/GCE and electrochemical detection of hexavalent chromiumIn this work,the PAMAM and CB NPs composite nanomaterials were modified on the electrode surface by covalent bonding.Compared with the pure carbon black,the composite material has improved the electrochemical signal of hexavalent chromium,and it has a good linearity in the linear range of 4 nM ~ 60 nM and 60 nM~ 500 ?M.The detection limit is 1 nM(S / N = 3).Therefore,PAMAM / CB NPs composite nano-materials because of its simple preparation method,can be used as a good electrode modifier,which is expected to be widely used.Third,electrochemical determination of cadmium and lead by bismuth nanoparticles / carbon black-chitosan modified glassy carbon electrodeIn this work,the CB nanoparticles were used to further increase the active surface area of the modified electrode,and the bismuth nanoparticles were introduced by the electrodeposition method to improve the sensitivity of the metal ions.The concentration of oxidation peak and the concentration of Cd2+solution were linear in the range of 20 nM-100 nM(R = 0.999),and the detection limit was 5.50 nM(S / N =3).The concentration of oxidation peak and Pb2+ solution were linear in the range of 4nM-10 nM and 10 nM-100 nM,and the detection limit was 0.86 nM(S / N = 3).The sensor has strong anti-interference,good reproducibility,low cost and good application in practical samples.