三维超分子化合物[H_2bpy]_2[SiMo_8~ⅥMo_4~ⅤV_2~ⅣO_(42)]·3H_2O的水热合成、表征及性质研究

Hydrothermal synthesis,crystal structure and property of a three-dimensional supramolecular compound [H_2bpy]_2[SiMo~Ⅵ_8Mo~Ⅴ_4V~Ⅳ_2O_(42)]·3H_2O

用硅钼酸做原料,在水热条件下合成了一种新型的三维超分子化合物[H2bpy]2[SiMo8ⅥMo4ⅤV2ⅣO42].3H2O.该化合物属于单斜晶系:C2/c空间群;化学式为C20H26Mo12N4O45SiV2,相对分子质量为2 323.62;晶胞参数a=1.427 9(7)nm,b=1.901 2(4)nm,c=2.091 4(9)nm,β=97.73(6)°,V=5.626(5)nm3,Z=4.在该化合物中,水的二聚体通过氢键作用将二帽Keggin多阴离子连接起来,形成三维超分子框架.同时,也研究了将该化合物修饰到电极的电化学行为,表明电极过程是由表面控制的.

A new polyoxometalate - based three - dimensional supramolecular compound, [H2bpy]2[SiMo8^ⅥMo4^ⅤV2^ⅣO42]·3H2O, has been hydrothermally synthesized by using pre- synthesized H4SiMo12O40 as building block. It crystallizes in the monoclinic system, space group C2/c, a = 1. 427 9（7） nm, b = 1. 901 2（4） nm, c = 2. 091 4（9） nm, β = 97.73（6）°, V = 5. 626 5（8） nm^3 and Z = 4. The compound represents the first example of hydrogen - bonded three- dimensional framework in which bicapped Keggin polyoxoanions are linked together by water- dimer through hydrogen bonds. The compound was used as a bulk - modifier to fabricate a chemically modified carbon paste electrode （CPE） by direct mixing. Its electrochemical behavior was studied at the same time.