Fabrication And Application Of Cadmium Sulfide Nanoparticles Chemically Modified Electrode

Cadmium sulfide(CdS), one of the most important and populargroup II—IV semiconductors, has a large band gap of 2.4eV at roomtemperature ,which nanostructures have also attracted muchattention in recent years because of the excellent optical andelectrical properties．Currently, study on the properties andfabrication of CdS nanomaterials become more and morepopular．These properties of CdS nanomaterials make them widelyused in the field of photo absorption, photochemical catalysis, solarcells, nonlinear optics, lasers, photoelectric diodes, thin filmtransistors, field effect transistor (FET) , logic circuits, and sensorsetc.. The CdS nanomaterials can be prepared by physical andchemical methods, such as solid state reaction, microemulsion,chemical bath deposition and electrodeposition. In this paper, theCadmium sulfide nanoparticles modified glassy carbon electrode wasprepared. Besides, the modified electrode is taken into the study onpollutants in the environment and iodine-containing drugs.The details are summarized as follows:1. Preparation of Cadmium sulfide nanoparticles modified glassycarbon electrode and its application to the determination of catechol. In this paper, CdS nanoparticles (CdSNPs) have been successfullysynthesized via a facile ultrasonic method and characterized byscanning electron microscope (SEM).The CdSNPs were immobilizedon glassy carbon electrode to fabricate a novel modified electrode.The electrochemical behavior of catechol was investigated on theCdS nanoparticles modified electrode. The effects of the type andacidity of electrolytes were studied, and KH2PO4-boxra buffer solution(pH 6.4) were selected as the supporting electrolyte. Experimentalresults showed that catechol could be oxidized in modified electrode.The linear range for catechol determination ranged from 4.0×10-3mol/Lto 3.0×10-6mol/L with a detection limit of 5.5×10-7mol/L. Furthermore,the modified electrode exhibited good repeatability and stability,which can be used for determination of catechol.2. Electrochemistry investigation of Cd(Ⅱ) at Cadmium sulfidenanoparticles modified glassy carbon electrode and itselectroanalysis application.In chapter 3, the electrochemistry behavior of cadmium ions in theCadmium sulfide nanoparticles modified glassy carbon electrode wasdiscussed and displayed a good stripping peak. The responsemechanism is discussed in the paper. Anodic stripping voltammetrywas developed for the determination of trace cadmium. Theexperimental parameters such as the accumulation time,accumulation potential and supporting electrolyte, were investigated.The results showed that the liner range for Cd（Ⅱ）determination rangefrom 1.0×10-4mol/L to 2×10-7mol/L with a detection limit of 5×10-8mol/L.The modified electrode showed strong anti-interferenceability, and can be used for the determination of cadmium in the wastewater.3. Electrochemistry investigation of I-at Cadmium sulfidenanoparticles modified glassy carbon electrode and itselectroanalysis application.In chapter 4, the electrochemistry behavior of iodide ions in theCadmium sulfide nanoparticles modified glassy carbon electrode wasdiscussed. Cyclic voltammetry was developed for the determinationof iodide ions in 0.5mol/L H2SO4.The result showed that the modifiedelectrode apparent catalytic oxidation of iodide ion. The catalyticmechanism is discussed in the chapter. In the optimum experimentalconditions the peak current varied linearly with the concentration of I-over the range from 1.0×10-3mol/L to 3.0×10-6mol/L with a detectionlimit of 6.5×10-7mol/L. The modified electrode has been applied to theanalysis of iodine-containing drugs with a sactisfactory result.