| In this paper under hydrothermal conditions,eleven Keggin-type and isopolymolybdate polyoxometalates?POMs?-based compounds decorated by flexible bis?pyrazole?and flexible pendant ligands have been designed and synthesized.They are structurally characterized by elemental analyses,PXRD,IR,TG and Bruker Smart Apex II single crystal X-ray diffractions.The photocatalytic properties of these compounds have been studied as well.1.By using Keggin-type POMs as inorganic building blocks and metal organic unit constructed by transition metal Cu and flexible pendant ligands,we obtained two new compounds based on mono copper?II?-substituted phosphomolybdate.[Cu4?tea?6(H4PMo11CuO39)(PMo12O40)]2·33H2O?1?[Cu3?tea?6?H2O?2(H2PMo11CuO39)2]2·30H2O?2?tea = 2-[1,2,4]triazol-4-yl-ethylamineCompound 1 owns tetra-nuclear clusters [Cu4?tea?6],linking a pair mono copper?II?-substituted and saturated Keggin anions to form a 2D structure.Compound 2contains tri-nuclear clusters [Cu3?tea?6],fusing four mono copper?II?-substituted anions to construct a discrete four-membered cycle structure.2.By choosing Keggin-type POMs as inorganic building blocks modified by transition metal Cu and flexible bis-pyrazole ligands bis?3,5-dimethyl-1H-pyrazol-4-yl?methane,we obtained four new POM-based compounds.[Cu?H2bdpm?2?H2O?2(HPW12O40)]?3?[Cu?H2bdpm?2(H2PW12O40)]2·2H2O?4?[Cu2?H2bdpm?3?H2O?2(Si W12O40)]·2H2O?5?[Cu2?H2bdpm?4?H2O?(SiW12O40)]·17H2O?6?Compound 3 is a zero dimension?0D?structure,containing a [Cu?H2bdpm?2]2+mono-supporting [PW12O40]3-anion.The anions in compound 4 shows two coordination modes:?1?the anion POM1 links two [Cu?H2bdpm?2] to form a “H”-type bisupporing structure;?2?a discrete POM2 anion.When the [H3PW12O40] was insteaded by[H4SiW12O40],compounds 5 and 6 were obtained.Compound 5 contains bi-nuclear Cu2+cycles,which are linked by O4 W to form a cycle-connecting-cycle chain.The [SiW12O40]4-anions connect adjacent chains to construct a 2D structure.Compounds 6 contains a nested cycle subunit [Cu4?H2bdpm?6]8+,with two bi-nuclear cycles [Cu2?H2bdpm?2]4+linked by two H2 bdpm ligands.The nested cycle subunits are connected by H2 bdpm molecules toconstruct a 2D metal-organic layer.The Keggin anions link adjacent layers to form a 3D framework.3.By using 2-[1,2,4]triazol-4-yl-ethylamine?tea?,1,1'-bis?3,5-dimethyl-1H-pyrazol-4-yl?methane?H2bdpm?and 1,2-bis?1-H-pyrazolate?ethane)?H2bhpe?as ligands,different transition metal?Cu and Ag?and polyoxometallate as bulding units,we obtained five POM-based compounds.[Cu3K2?tea?2?OH?4(H2Mo8O27)]?7?[Ag?tea?(b-H2Mo8O260.5]?8?[Ag?tea??H2O?(g-H2Mo8O260.5]?9?[Cu?H2bdpm?(b-Mo8O260.5]?10?[Ag2?Hbhpe?(q-Mo8O260.5]?11?Compound 7 contains a tri-nuclear clusters [Cu3?tea?2?H2O?2]4+,which link [Mo8O26]4-poiyanion to construct a 3D framework.In compound 8,the Ag1 ions link b-Mo8 through Ag1-O1 bonds to construct a 1D chains.The adjacent 1D chains are still further linked by hydrogen bonding interations O5···Ag1 to construct a 2D supramolecular layer.In compound 9,the AgI ions link ?-Mo8 through Ag-O9 and Ag-O6 bonds to construct a 1D chain.The adjacent 1D chains are still further linked by hydrogen bonding interactions O1W···O7 to construct a 2D supramolecular layer.Compound 10 contains 1D zigzag Cu-H2 bdpm chains and 1D inorganic anion chains,in which these chains interconnect each other to build a 1D chain.The adjacent chains are just further linked by Cu1-O9 bonds to build a 2D structure.In compound 11,there exist a bi-nuclear [Ag2?Hbhpe?2]2-cycle and a tetra-nuclear [(Ag4?Hbhpe?4]4-cycle.The bi-nuclear [Ag2?Hbhpe?2]2-cycles link the tetra-nuclear [(Ag4?Hbhpe?4]4-cycles alternately to form a 1D metal-organic chain.The adjacent 1D metal-organic chains are further linked by q-Mo8 anions to construct a 2D layer.We have studied the photocatalytic activities of the title compounds,showing that compounds 1-4,6-11 own good photocatalytic activities for the degradation of MB and compounds 4-6,8-11 can act as good photocatalysts for the degradation of RhB.The electrochemical properties of 1-11 were also studied. |
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