Film Chemically Modified Electrode Research And Application

The chemically modified electrodes (CEM) have been a most burgeoningand one of the most flourish research realms in the electrochemistry andelectroanalytic chemistry. It was for the moment widely applied in manycases such as life science, environment science, energy source science ,a nalytic science ,electronics and material science. The filmchemically modified electrode are prepared by designing the electrodesurfaces on the molecule level and immobilizing the molecules ,ion andpolymers of the specifically chemical and electrochemical functions .Themediator modified on the surface of electrode can accomplish theelectrocatalytic reactions by accelerating electron transferring betweenredox centers and the electrode surface .The electro catalysis of themodified electrode is an enormous impetus for its development and iswidely used in the slow electron transferring processes which isn't easilyrealized ,for example, the electro catalysis of biomolecules,organic compoundsand inorganic ions.With specially chemical and electrochemical functionsthe modified electrode enriched the electrode materials and expanded theresearch fields of ehe electrochemistry. The preparations of the polymerfilms are very simple. The polymer film modified electrode also have manyother choiceness character which have been widely synthesized;thepolymer films usually have chemical,mechanical and electrochemicalstability;the thickness of films can be changed. So the polymer filmmodified electrode have very good development foreground on theapplication or research. Self-assembly as a new technique for thepreparation of organic ultrafilm was applied in various research fieldsby more and more investigations .Self-assembled monolayer (SAMS) is akind of single molecular layer which deposited on the surface of theelectrodes and other substrate surface, The specific property of themonolayer is that the molecules in the monolayer have a commondirection ,that is the molecules are well organized and oriented. It iswell known that calixarenes are a group of cavity-shaped cyclic moleculescomprising phonel units linked via alkylidene group. They possess specialcavity structure and thus are able to form host-guest inclusion complexeswith a variety of molecules selectively, if calixarenes were modified onthe electrode to form chemically membrane-modified electrodes, somemolecules with electrochemical characters may be separated each other.In our papers ,we made several modified electrode with specialfunctions by different methods such as Electrochemical sediment ,self-assemble and dropping, we also research the function of thoseelectrodes such as the ability of electrocatalyse , selection andadsorption at the same time we use those modified electrode to determinethe real products ,the whole paper includes four parts:First, 4-aminobenzenesulfonic modified glassy carbon electrode wasfirstly fabricated through electropolymerization. The high sensitivityand good selectivity were accomplished in the determination adrenaline(EP). The electrochemical behavior of adrenaline (EP) on the modifiedelectrode was investigated .The results of the experiment show that themodified electrode exerts an apparent catalytic effect on the EP oxidation.The method to make EP sensors is easy and convenient , The obtainedelectrode is prone to be reproducible, it also effectively avoided theserious interference from the ascorbic acid .Second, Poly-L-histidine and ferricyanide complex film modified glasscarbon electrode was firstly fabricated through electropolymerization. Theelectrochemical behavior of dopamine (DA) on the modified electrode wasinvestigated .Results show that the polymer exerts an apparent catalyticeffect on the DA oxidation and DA and AA can be separated effectively.Third, A new chemically modified Ag electrode was made by usingL-cystein as a modifier, the electrochemical behaviors of zinc(Ⅱ) ionon self –assembled monolayer L-cystein modified Ag electrode have beenstudied. A new approach was developed for sensitive and accurativedetermination of zinc by the electrode.At last, Novel glass carbon electrode modified by calixarenes wasfirst prepared, Voltammetric characteristic of the modified electrode andapplication in recognition of Cd2+ and Hg2+were investigated in acidsolution . The result shows that the modified electrode has a sensitiveresponse to Cd2+ and Hg2+ ions.