| Polyoxometalates（POMs）have been widely applicated in electrochemistry,catalysis,magnetic and medicinal chemistry owing to their fascinating structure and attractive physicochemical properties.With the booming of POMs chemistry,organic-inorganic hybrid materials,a series of unique compounds formed by introducing organic compounds into POMs,have become one of the focuses of polyoxometalate chemistry.As an important section in organic-inorganic hybrid materials,charge transport salts have also received extensive attention and research.In this thesis,twenty-one new compounds have been synthesized via water solution synthesis methods,and structurally characterized by IR,elemental analyses,UV-visible diffuse reflectance spectroscopy,surface photovoltage spectrum,etc..1.Twelve new compounds 1-12 based on electron acceptors—saturated Keggin and Dawson type polyoxometalates—with electron donors,including naphthyl ethylenediamine hydrochloride,N-phenyl-p-phenylenediamine and benzidine hydrochloride,have been synthesized and structurally characterized.[(C14N2H15)2H]PW12O40·16H2O（1）[(C14N2H15)2H]PMo12O40·10H2O（2）[(C14N2H15)4H2]P2W18O62·3H2O（3）(C14N2H16)3P2Mo18O62·10H2O（4）[(C12N2H13)2H]PW12O40·4H2O（5）[(C12N2H13)2H]PMo12O40·12H2O（6）(C12N2H13)6P2W18O62·24H2O（7）(C12N2H13)6P2Mo18O62·17H2O（8）(C12N2H14)3[PW12O40]2·11H2O（9）[(C12N2H13)2H]PMo12O40·10H2O（10）(C12N2H14)3P2W18O62·8H2O（11）(C12N2H14)3P2Mo18O62·13H2O（12）The characteristic peaks of organic compound and POM can be found from the infrared spectrum,indicating that the POM anion still retain original skeleton in the compound.Within the scope of visible light,new peaks can be found from UV-visible diffuse reflectance spectrum,which are attributed to the charge transfer from organic conjugated π-electron to POM.These new peaks also prove the existence of W（VI）→W（V）or Mo（VI）→Mo（V）.In addition,the results of the bandgap calculation show that the bandgap values of the compounds have a significant decrease relative to their organic reactant.Cyclic voltammetry test indicates that the charge transfer compounds remain the electrochemical properties of the POM and show good electrocatalytic properties towards the reduction of nitrite.2.By using alcian blue as electron donor,Keggin and Dawson type polyoxometalates as electron acceptors,five new compounds 13-17 have been synthesized and structurally characterized.(C56H71N11S4Cu)2H[PW12O40]5·70H2O（13）(C56H71N11S4Cu)2H[PMo12O40]5·54H2O（14）(C56H72N11S4Cu)4H[P2W18O62]3·14H2O（15）(C56H75N11S4Cu)4H[P2Mo18O62]5·88H2O（16）(C56H75N11S4Cu)5H[P2W15O56]3·132H2O（17）The characteristic peaks of alcian blue and POM can be found from the infrared spectrum,indicating that the skeleton of POM anion has not changed.New peaks within the scope of visible light in UV-visible diffuse reflectance spectrum show the charge transfer from organic conjugated π-electron to POM,which also proves the existence of W（VI）→W（V）or Mo（VI）→Mo（V）.By calculating bandgap values of the new compounds,we find that they are getting closer to alcian blue.3.By using [Ni（Me6[14]-4,11-diene N4）]（Cl O4）2 as electron donor,saturated Keggin and Dawson type polyoxometalates as electron acceptors,we synthesized and structurally characterized four new compounds 18-21.(Ni C16N4H32)2[PW12O40] Cl O4·10H2O（18）(Ni C16N4H32)2[PMo12O40] Cl O4·19H2O（19）(Ni C16N4H32)3P2W18O62·36H2O（20）(Ni C16N4H32)3P2Mo18O62·26H2O（21）The peaks of both organic compound and POM can be found from the infrared spectrum,which means POM anion still retain the same in the compound.We can also find new peaks in UV-visible diffuse reflectance spectrum within the rage of visible light,showing that the organic conjugated π-electron transferred to POM.By calculating the band gap,we can see that the bandgap values of new compounds have an obvious decrease relative to [Ni（Me6[14]-4,11-diene N4）]（Cl O4）2.Cyclic voltammetry result indicates that these charge transfer compounds still have the electrochemical properties of POM and have good catalytic activity for nitrite. |
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