The Preparation Of High Sesitive Composite Film Electrode And Its Appliation

The preparation and application of three dimensionally ordered maeroporous(3DOM) materials has become the popular research in materials science, because theyhave not only three-dimensional network path and uniform pore sizes leading to easyaccessibility for large compound, but also porous texture generating large specificsurface area. Three-dimensionally ordered macroporous (3DOM) films aretechnologically important for a variety of applications, including photonic crystals,catalysts, supports, separation systems, sensors, adsorbents, electronic materials,double-layer capacitors, and hydrogen-storage materials.3DOM films possess the open,interconnected, periodic large porous structures, which ensure accessibility of reactantsto the active sites on the surface of the electrode that brings to the electrochemical goodprospects.In this paper. Monodisperse polystyrene (PS) beads were prepared by using novelcolloidal crystal template. L-cysteine oxide film have been introduced into the wallframework by vertical deposition technique through templates assembled fromsubmicrondiameter monodisperse polystyrene spheres. L-cysteine oxide film wereprepared by cyclic voltammetry method deposited in supporting electrolyte within theinterstitial spaces between polystyrene latex spheres (350nm in diameter) assembled onglassy carbon electrode (GCE) surfaces. The latex sphere templates were subsequentlyremoved by dissolving in toluene to leave the structured metal films. Thethree-dimensionally ordered macroporous (3DOM) L-cysteine oxide film (LCO) wasmodified on the glassy carbon electrode surface. Scanning electron microscopy (SEM)to characterize the three-dimensional ordered macroporous results show that3DOM-LOC/GCE surface neatly arranged by regularly enrich hole tunnel. Theelectrochemical properties of the modified electrode were characterized usingK3[Fe(CN)6] as electrochemical probes between two-dimensional probe compares andthree dimensionally ordered maeroporous. The redox signal on3DOM-LCO/GCEresponse and significantly enhanced, aslo potential difference between the peak whichnarrowed the range, The difference between the peak potential explanation thatstandard heterogeneous rate constant increases and the effective electrode area muchbigger, experiments show that3DOM-LOC modification of the film is an excellentmaterial, which increases the more the reaction of reactive sites. In order to investigate the three-dimensional ordered macroporous film modifiedelectrode that performances to environmental hormone substances4-chlorophenol and4-aminophenol to detect objects. We found that the oxidation signals of4-chlorphenolwas further improved on surface of3-DOM polycysteine filmmodified GCE. Theoxidation signals improvement clearly reveal that the prepared3-DOM polycysteinefilm is more active for detection of4-chlorphenol. the effects of pH value, andaccumulation potential and time were studied, Finally, a sensitive, rapid and convenientelectrochemical method with a good linear relationship in the range5.0×108to5.0×106mol/L, and the limit of detection is as low as1.67×108mol/L. Compared with thereported electrochemical methods for4-chlorophenol detection, this new sensordisplayed high sensitivity. The electrochemical behavior of4-aminophenol wasinvestigated using cyclic voltammetry and differential pulse voltammetry at the3DOMLCO/GCE. In comparison with GCE,3DOM-LCO/GCE shows much larger peakcurrent which may be related to the structure of L-cysteine oxide and the large surfacearea of the nanopore array structure. Under the optimized condition, the anodic peakcurrent was linear with the concentration from0.02to200μM with a detection limit of0.008μM (S/N=3). Also suggesting that the redox reaction of4-aminophenol at the3DOM-LCO/GCE should be a two electrons and two protons process. The proposedmethod was successfully applied to the determination of4-aminophenol in watersamples, and the results are satisfactory.Acetylene black (AB), a special kind of carbon black materials were readilydispersed in chitosan (CST). And the surface of glassy carbon electrode (GCE) wasmodified by the obtained mixture to prepare acetylene black-chitosan modified glassycarbon electrode (AB-CTS/GCE). The K3[Fe(CN)6] solution characterization resultsshowed that AB-CTS/GCE can effectively improve the electronic transmission rate.Electrochemical behavior of Sunset Yellow was studied, and a sensitive oxidation peakwas observed in pH7.0phosphate buffer solution. Compared with the bare GCE, theAB-CST modified GCE greatly increased the oxidation peak current of sunset yellow,showing remarkable signal enhancement effect. The influences of pH value, amount ofAB, accumulation potential and time on the signal enhancement of sunset yellow werestudied. The linear range was from5.0×10-8mol/L～1.0×10-5mol/L, and the detectionlimit was9.0×10-9mol/L after3min accumulation. As a result, a novelelectrochemical method was developed for the determination of sunset yellow. It was applied to the detection of sunset yellow in commercial soft drinks. In addition to this,In the presence of dihexadecyl hydrogen phosphate(DHP), the insolube acetylene black(AB) was dispersed into water under ultrasonic condition, the dispersion stabilityacetylene black film modified electrode was achieved. The electrochemical behavior ofquinoline yellow at AB-DHP film modified electrode was investigated in detail. TheAB-DHP composite film modified electrode oxidation signal significantly improved byoptimizing the assay conditions, the linear range of the method was0.5~20mg/L, thedetection limit of0.12mg/L (2.514×10-7mol/L), It is applied to detect the actualbeverage samples, The average recovery was102.28%.