| In-situ assembly–step-by-step synthesis strategy has more explicit design and guidance than the traditional one-pot aqueous solution method.By using this strategy,we prepared several series of transition-metal?TM?–rare-earth?RE?heterometal containing polyoxomolybdates and organotin–RE heterometal containing tungstoantimonates,which were further structurally characterized by elemental analyses,IR spectra and single-crystal X-ray diffraction.The magnetic properties,fluorescence properties,electrochemical and photodegradation performances of the related compounds were also investigated.This work not only provides an effective method for preparing novel heterometal containing polyoxometalates,but also enriches the structural types of polyoxometalates and extends the research field of metal-oxo cluster chemistry.This dissertation is divided into the following three sections to introduce my work during master degree study:Part I.By in-situ assembly–step-by-step synthesis strategy and the controlling role of RE cations,we prepared two classes of organic–inorganic hybrid Mn–RE incorporated polyoxomolybdate derivatives?NH4?8{[RE?Hina??ina??H2O?2][MnIVMo9O32]}2·12H2O[RE=La3+?1?,Pr3+?2?,Nd3+?3?]and?NH4?3[RE?Hina?2?H2O?6][MnIVMo9O32]·7H2O[RE=Sm3+?4?,Eu3+?5?,Gd3+?6?,Tb3+?7?,Dy3+?8?,Ho3+?9?,Er3+?10?,Tm3+?11?,Yb3+?12?,Y3+?13?]?Hina=isonicotinic acid?.1–13 were synthesized based on?NH4?6(Mo7O24)·4H2O,Mn?CH3COO?2·4H2O,30%H2O2,Hina and RE?NO3?3·6H2O.1–3 display the dimeric structures constructed from two[MnMo9O32]6-fragments bridged by Hina-RE complex ions,whereas 4–13 demonstrate isolated structures.1–13 represent the first examples of RE–organic units containing Waugh-type manganomolybdates so far.1–13 exhibit the good photodegradation activity towards azophloxine.The near-infrared fluorescence emission spectrum of 3 reveals the characteristic emission peaks of the Nd3+ions.The UV–visible fluorescence emission spectra of 4 and 5 show the characteristic emission peaks of both RE and Mn4+ions,respectively.Part II.By using different heteroatoms,two types of organic–inorganic hybrid Cu–RE heterometal containing germanomolybdates and silicomolybdates were successfully isolated by the in-situ assembly–step-by-step synthesis strategy in the aqueous solution[H2INA]2[NH4]8[RECu?HIN?4?H2O?6]2[?-GeMo12O40]3·52H2O[RE=La3+?14?,Ce3+?15?,Pr3+?16?,Nd3+?17?,Sm3+?18?,Eu3+?19?]and[H2INA]2[NH4]8[RECu?HIN?4?H2O?6]2[?-SiMo12O40]3·54H2O[RE=La3+?20?,Ce3+?21?,Pr3+?22?,Nd3+?23?,Sm3+?24?,Eu3+?25?]?Hina=isonicotinic acid?.14–25 were synthesized based on the simple materials RE?NO3?3·6H2O,?NH4?6(Mo7O24)·4H2O,CuCl2·2H2O,GeO2/Na2SiO3·5H2O and Hina ligands.14–25 are discrete structures and represent the first examples of 3d–4f heterometallic saturated Keggin-type germanomolybdates/silicomolybdates.In addition,16 as a photocatalyst can to some degree prohibit the photodegradation of several organic dyes such as azophloxine,methyl orange,methylene blue and gentian violet.Part III.By the in-situ assembly–step-by-step synthesis strategy,we obtained two family of organotin–RE substituted tungstoantimonate derivatives[RE?H2O?6][Sn?CH3?2?H2O?]2[Sn?CH3?2][B-?-SbW9O33]·8H2O[RE=La3+?26?,Ce3+?27?,Pr3+?28?,Nd3+?29?,Sm3+?30?]and[RE?H2O?6?pca?]H[Sn?CH3?2?H2O?]3[B-?-SbW9 O33]·12H2O[RE=La3+?31?,Ce3+?32?,Pr3+?33?,Nd3+?34?,Sm3+?35?]?Hpca=pyridine-4-carboxylic acid?.26–35 were prepared by reaction of the trivacant Keggin-type[B-?-SbW9O33]9–precursor with organotin groups,RE ions and organic ligands.26–35 are the first organotin–RE heterometallic tungstoantimonates.The preparations of 26–35 not only enrich the structural types of polyoxometalates,but also extend the research field of polyoxometalate chemistry.The near-infrared fluorescence emission spectra of 28–30 and 33–35 exhibit the characteristic emission peaks of corresponding RE ions.The UV-visible fluorescence emission spectra of30 and 35 display the characteristic emission peaks of Sm3+ions. |
PDF Full Text Request