Preparation Polyoxometalates Compound Modified Electrodes And Study Of Their Elecreochemical Properties

Polyoxometalate compound has a history of more than one hundred years since it has been found. Due to its well electrochemical catalytic, it has been used in eletrochemical modified electrodes, widely. In this thesis, we have prepared new polyoxometalate compound modified electrode by using the method of electrodeposit. The material of the modified electrode are porous anodic aluminum oxide membranes(AAO), graphene oxide(GO) and polyoxometalate compound. We used the X-ray diffraction(XRD), Scanning Electron Microscope(SEM) and solide-urtraviolet(UV) to character the modified electrodes.We also studied the electricatalytic of the modified electrodes by using the cyclic voltammetry(CV) and other electrochemical means.Firstly, we prepared a new inorganic/organic modified electrode, PMo12-PPy/AAO/Al.The SEM image of AAO/Al showed the AAO is composed of hexagonal unit cell and a micropore in the middle of the cell. From the SEM image of PMo12-PPy/AAO/Al we can see the PMo12-PPy is deposited in the pore of AAO/Al as the style of Nano ball.Experiments result showed that PMo12-PPy was evenly deposited. The electrochemical properties of the new material electrode are exhibited clearer CV with three reversible to NO2- and pyrocatechol(CC). The linear response of NO2- and CC are obtained limits were estimated to be 0.48 μM, for NO2-and 79 n M for CC with the signal-to-noise ratio of 3(S/N). This sensor exhibits superior stability and good ability of anti-interference to electroactive molecules.Secondly, we used GCE as modified electrode base, modified graphene oxide(GO) on the GCE by the method of electrodeposit to prepared the P2W18/ GO/PDDA/GCE. The SEM images of P2W18/GO/PDDA/GCE and GO solution we can see the GO on the modified electrode and GO dispersion have the similar style. It can prove we have modified GO on the PDDA/GCE. We characterize the electrocatalytic of the P2W18/GO/PDDA/GCE in the H2SO4 solution(p H=2), scan rate is 50 m V/s. P2W18/GO/PDDA/GCE show high sensitivity and on the NO2-, H2O2, dopamine(DA), catechol(CC) and hydroquinone(HQ). The linear response of DA is obtained limits were estimated to be 3×10-9M, especially.P2W18/GO/PDDA/GCE can detect the CC and HQ at the same time.