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Carbon nanotubes（CNTs） as a unique structural high molecular material haveseveral advantages, such as large specific surface area, strong adsorptive property,high electrical conductivity and excellent optical property. CNTs are extensivelyapplied to all kinds of aspects, such as nano-electronical devices, high-performancesensors, electrode materials, and have good application prospect. Metalnanoparticles play extremely significant role in chemical sensing, catalyst,pharmaceuticals and other fields. Noble metal nanoparticles with gold and palladiumnanoparticles as the representative have the merits, such as small particle size, goodstability and high catalytic performance. Nowadays, as the study of metalnanoparticles deeply developing, there are numerous methods which prepare metalnanoparticles,such as gold and palladium. However, some researchers begin to payhigh attention to prepare the bimetallic nanoparticles and other complicatedstructural composite nanoparticles. Metal nanoparticles play the important role inthe development of industrial manufacturing and high-tech research. In this thesis,the glassy carbon electrode modified with CNTs and metal nanoparticles is studied inits electrochemical measurement and application.I．The preparation of glassy carbon electrode modified with ferroferricoxide-carbon nanotubes nanocomposite and its application for the electrochemicaldetermination of bisphenol AIn this study, a novel method for electrochemically determinating BPA wasestablished with ferroferric oxide-carbon nanotubes nanocomposite as modifiedmaterial. The cyclic voltammetry, impedance method, chronoamperometry andother electrochemical characterizations and measurements were used.Theexperimental result showed that the modified electrode （Fe3O4NPs/MWNTs/GCE）could remarkably enhance the oxidation peak current of bisphenol A, and whichwas as three times as GCE’s. This method exhibited the property of quickness,simplicity and sensitivity. The concentration of BPA was good linear with the oxidation peak current in the range from0.1μM to1μM, and got the detection limitof50nM （S/N=3）. This sensor also achieved the nice result of determinating BPA inreal water sample, and had the promising prospect.II．A novel electrochemical sensor based on glassy carbon electrode modifiedwith AuPd NPs/MWNTs for the determination of L-cysteineIn this thesis, a sensitive and reliable electrochemical method for detectingL-cysteine was built with AuPd NPs-MWNTs nanocomposite as modified material ofglassy carbon electrode. The study demonstrated that AuPd NPs and MWNTsnanocomposite obviously improved the current response and detection sensitivity.Through optimizing pH value, scan rate, electrodeposition time of AuPd NPs andother experimental parameters, the concentration of L-cysteine was good linear withthe oxidation current in the range from0.1μM to10μM, and a detection limit of10nM （S/N=3） was obtained. This method was successfully applied to detect L-cysteinein different conditions, and the detection result was satisfactory.III．The electrochemical determination of Cr（VI） based on glassy carbonelectrode modified with PdNPs and MWNTsIn this thesis, the glassy carbon electrode modified with Pd NPs and MWNTs wasapplied to the electrochemical determination of Cr（VI）. We characterized modifiedelectrode with field-emmission scanning electron microscope, cyclic voltammetry, ACimpedance, differential pulse voltammetry and other techniques. The studydemonstrated that a large number of metal ions, such as Cr3+, Pd2+, Zn2+, Pb2+,Cu2+, Al3+, Ba2+, Ca2+, Mg2+, had no interference with the determination of Cr（VI）.The reduction peak current of Cr（VI） was good linear with its concentration in therange from0.05μM to0.8μM, and got the detection limit of27nM （S/N=3）.Compared to other existing methods, this one had the excellent properties ofconvenience, quickness, good selectivity and high sensitivity.
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