| Polyoxometalates?POMs?are a unique and important class of anionic oxide clusters.Especially in recent decades,highly polymerized,nano-sized,pore shape and organic-inorganic modified polyoxometallates have broken through the research scope of classical POMs,injecting new impetus into the development of POMs,and these novel POMs have the characteristics of acid-base,lipophilic and organic-inorganic components.Additionally,it has also been proved in the report that polyoxometalates can effectively deal with the water pollution,exhibiting specific selectivity,high efficiency,reusability and structural stability as catalysts.Therefore,on the bases of previous work,it is of great theoretical significance to explore the synthesis of novel polyoxometallate compounds.In the present paper,eight new compounds[Ni2?L1?3]2[W6O19]·2H2O?1?,[Cu?HL1?2]2[?-Mo8O26]·10H2O?2?,[Co?L1?2]2Na2[?-Mo8O26]·9H2O?3?,[Fe?L1?2]2Na2[?-Mo8O26]·9H2O?4?,[Ni?HL2?H2O]2[Mo8O26]·2H2O?5?,[Ga?HL3?]2[Mo7O24]·15H2O?6?,[Co?HL3??L3?]4H2[CoMo12O40]·6H2O?7?,?H2L3?4[Mo8O26]·5H2O?8?were synthesized based on2-acetylpyrazine-N?4?-methyl thiosemicarbazone?HL1?,2-acetylpyrazine thiosemicarbazone?HL2?,2-acetylpyridine thionsemicarbazone?HL3?.At the same time,the basic characterization,catalysis,adsorption and antibacterial properties of the prepared compounds were studied.In chapter 1,four compounds[Ni2?L1?3]2[W6O19]·2H2O?1?,[Cu?HL1?2]2[?-Mo8O26]·10H2O?2?,[Co?L1?2]2Na2[?-Mo8O26]·9H2O?3?and[Fe?L1?2]2Na2[?-Mo8O26]·9H2O?4?were synthesized by using2-acetylpyrazine-N?4?-methyl thiosemicarbazone?HL1?as organic ligand.The different dyes were used to evaluate the adsorption properties of compound 1.Taking the methylene blue?MB?for an example,and the possible mechanism for the adsorption process of different concentrations methylene blue were fitted by kinetic equation.For the compounds 2–4,the photocatalytic properties of different light sources were compared.In addition,the catalytic activity was also studied,compounds 2–4 as catalyst are explored in the oximation of aldehydes and ketones with in situ generated hydroxylamine by a one-pot procedure.The results demonstrated that compounds 2–4 display high catalytic activity and selectivity for the oximation of ketones and aldehydes.In chapter 2,2-acetylpyrazine thiosemicarbazone?HL2?reacting with?NH4?2Mo7O24·4H2O formed compound[Ni?HL2?H2O]2[Mo8O26]·2H2O?5?.By catalyzing the epoxidation of olefins,compound5 displayed high catalytic activity.Then,compound 5 was evaluated for its adsorption properties on different dyes,and the kinetic equation was used to fit the adsorption mechanism of different concentrations of methylene blue.In addition,the antibacterial properties of compound 5 against Escherichia coli and Staphylococcus aureus were studied,and parallel comparison experiments were carried out on the raw materials.The experimental results revealed that the antibacterial activity of the single raw material is weak,while the compound 5 shows better antibacterial property.In chapter 3,reactions of Ga?NO3?3·6H2O,Co?ClO4?2·6H2O,NaMoO4·2H2O,MnCl2·2H2O with 2-acetylpyridinethiosemicarbazone?HL3?asrawmaterialsobtainedcompounds[Ga?HL3?]2[Mo7O24]·15H2O?6?,[Co?HL3?2]2[CoMo12O40]·6H2O,?H2L3?4[Mo8O26]·5H2O?8?,respectively.The antibacterial properties of compounds 6–8 against Escherichia coli and Staphylococcus aureus were studied.Parallel comparison experiments between HL3 and Ga?NO3?3·6H2O/Co?ClO4?2·6H2O were carried out.The results indicated that the single metal had no obvious antibacterial activity,and the antibacterial effect of the ligand was relatively weak,while the compounds 6 and 7 showed good antibacterial property,the compound 8 had no obvious antibacterial activity in the bacteriostatic test,which indicated that the antibacterial activity may be related to metal ions and ligands.In addition,we also studied the photocatalytic activity of compounds 6–8 on MB,FB,GV,T and MO.Aparting from MO,the results revealed that compounds 6–8 had better selectivity for different dyes and better degradation. |
PDF Full Text Request