| {P6Mo18}Basket-type polyoxometalates are atypical polyoxometalates?POMs?with more surface oxygen atoms than the most classic Well-Dawson type,unique topology,and Good reversible multi-electron transfer characteristics,so it is an excellent pHotocatalytic material.At present,there are few reports of such compounds,which may be due to the instability of the intermediates forming the basket clusters,which are difficult to prepare from solution.Therefore,by adjusting different pH values,selecting different organic ligands and transition metals,and fully utilizing the action of alkali metal templating agents,five kinds of unrecognized zero-dimensional basket-type pHospHomolybdates were synthesized by hydrothermal synthesis.A novel one-dimensional basket type pHospHomolybdate derivative.According to elemental composition analysis and single crystal X-ray diffraction analysis,their chemical formulas are determined as follows:?H4dih??H3dih?[{(K???P6Mo18O73)}]·3H2O)?1?,?H2bie?2?H2py?2[{CuI?Hbis?2{Cu??H2O?}{K???P6Mo2VMo16?O73}2]·9H2O?2?,?H2bipy?8[{Sr???P6Mo2VMo16?O73}]·7H2O?3?,?H2bpy?3[{Sr???P6Mo18O73}]·6H2O?4?,?H2bpy?9[{Mn8?H2O?2?H2O?3}{Sr???(P6Mo2VMo16?O73}2{Sr???(P6Mo3VMo15?O73}2]·18H2O?5?,?H2die?3[{Sr?H2O?4}{(Sr???P6Mo18O73)}]·4H2O?6?,?H2die?3[{Mn2?H2O?5Sr???P6Mo4VMo14?O73}]·7H2O?7?,?H2btp?3[{Cu??H2O?}{Sr???P6Mo2VMo16?O73}]·4H2O?8?,dih=1,6-di?1H-imidazol-1-y?hexane dihydrogen,die=1,2-di?1H-imidazol-l-yl?ethane,bte=1,2-Bis?1,2,4-triazol-1-y?ethane,btp=1,3-Bis?1,2,4-triazol-1-y?propane,bipy=2,2?-bipyridine,bpy=4,4?-bipyridine).Through crystal structure analysis:Compound 1 is a basket-type supramolecular network induced by potassium as a template and flexible ligand;Compound 2 is a modified by{CuI?Hbis?2}complex formed by Cu2+acting as a linking unit.Polymer clusters;compound 3 and 4 are supramolecular compounds modified with an organic ligand using ruthenium as a template;compound 5 is a mixture of four basket-type polyacids from four binuclear complex{Mn2?H2O?n}units The first synthetic tetragonal tetramer cluster with two unique pores is the first basket of high-concentration derivatives;compound 6 is a one-dimensional basket compound modified by alkaline earth metal ruthenium as a bridging unit.Compounds 7 and 8 are"Z"-shaped one-dimensional chain basket compounds in which transition metal manganese and copper are connected units,respectively.The capacity of the basket-type polyacid complexes as the ruthenium electrode was studied for the first time.Compounds 1-8 exhibited high capacitance and good stability.The experimental results showed that the capacity of the basket tetramer 5 was higher than that of the sample?1865?.In addition to the seven basket compounds,the capacitance of the three one-dimensional chain structures is higher than that of the zero-dimensional basket compound.This is because in the tetramer and one-dimensional chains,the substitution of the transition metal promotes electron and ion transfer and improves.The efficiency of electron transport,in addition to the larger pores in the tetramer structure,provides space for electron transport,increasing the specific surface area of the material,thereby increasing the capacitance.Electrocatalytic performance studies show that{P6Mo18}basket-type polyoxometalate hybrid materials have dual-function catalysis,which can catalytically reduce hydrogen peroxide and catalytically oxidize bio-organic molecule ascorbic acid.It is a promising bifunctional catalyst.The one-dimensional basket-type compound has better catalytic effect than the simple zero-dimensional compound,which may be due to the fact that the bridged transition metal increases the electron transport efficiency and the steric hindrance.Studies on pH otocatalytic properties show that compounds 1-8 have good pHotocatalytic activity for the common organic dyes methylene blue,rhodamine B and methyl orange under ultraviolet light.Compared with other classic polyacid salts,it has the advantages of good catalytic effect,short degradation time and thorough degradation.In addition,under the same conditions,the same basket compounds have different effects on the degradation of different dyes,which may be due to the different reaction pathways of different dyes,which lead to different degradation behaviors of different substrates. |
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