Based On Keggin Type Organic Inorganic Acid And Organic Dyes More Complex Compound Of Chemically Modified Carbon Paste Electrode And Electric Catalytic Research

Polyoxometalates (POMs) have the ability to obtain mutil electron redox process, which promote POMs to be an excellent candidate for electrocatalysis. However, POMs as a catalyst are easily to dissolve in water and unstable in the reaction system. The electrode modified by the POMs is made by the traditional method having a lower reusage rate. Organic dye (methylene blue (MB) and new methylene blue (NMB)) as a kind of cation have large π-electron planar, which can form inorganic-organic hybrid materials with POMs. These inorganic-organic hybrid materials are highly stable and undissolved in water, which can overcome the shortcomings of POMs in the reaction system. At the same time, chemically modified carbon paste electrode (CMCPE) as a novel method has a lot of advantages, such as, it is easily made and the surface of the electrode can be renewed.Six inorganic-organic hybrid materials based on organic dye and polyoxometalates have been synthesized, and characteried by IR, Elemental analysis and Solid diffuse reflectance spectrum.Inorganic-organic hybrid materials based on MB and Keggin-type POMs:[C16H18N3S]4[PMo12O40]·2DMF·H2O(1)[C16H18N3S]4[SiMo12O40](2)[C16H18N3S]4[GeMo12O40](3)Inorganic-organic hybrid materials based on NMB and Keggin-type POMs:[C18H22N3S]4[PMo12O40](4)[C18H22N3S]4[SiMo12O40](5)[C18H22N3S]4[GeMo12O40](6)We have used these inorganic-organic hybrid materials as modification to prepare six carbon paste electrodes (CPE), respectively. Voltammetric behavior research, in1M H2SO4, has indicated that all these CPEs have three pairs of redox peaks, which can be attributed to the three consequent two electron redox process, and these CPEs show remarkable stability after500circles, and squeezing a little carbon paste from these CPEs can be renewed the bulk-modified CPE when needed.The electrocatalysis ability of theses CPEs toward chlorate, bromate, nitrite and hydrogen peroxide in the1M H2SO4has been studied, and the electrocatalysis ability of the Keggin-type POMs is:[PMo12O40]4->[SiMo]2O40]4->[GeMo12O40]4-.In the1M H2SO4, the mean peak potentials of4-CPE,5-CPE and6-CPE are lower than corresponding those of1-CPE,2-CPE and3-CPE’s at the scanning rate20mV s-1, respectively. However, the different values are small. All these results may be ascribed to the difference of organic dyes in the CPEs.