含Keggin类型多酸单元和2-吡啶甲酸的杂化材料的合成、结构及表征

Fabrication of Hybrid Materials Containing Keggin‑Type Polyoxometalates Units and 2‑Picolinic Acid:Synthesis,Structures and Properties

合成了2例基于2⁃吡啶甲酸(2⁃PA)和Keggin类型[SiW12O40]^4-、[PMo12O40]^3-多酸单元的有机-无机杂化材料:H2[(CH3)4N]6[Cu(2⁃PA)2(SiW12O40)2](1)和(H3O)[Cu6(2⁃PA)9(PMo12O40)(NO3)](2),并用红外光谱以及X射线衍射对其进行了表征。单晶衍射结构分析表明化合物1为单斜晶系,空间群为P21/c,不对称单元中包含1个二价铜离子、2个2⁃吡啶甲酸配体以及2个Keggin类型[SiW12O40]^4-多酸单元并组成零维结构。循环伏安测试表明化合物1在扫速为100 mV·s^-1时,3组半波电位分别为-270、-516、-708 mV。化合物2为三方晶系,空间群为R3c,不对称单元中包含2个晶体学独立的二价铜离子并且具有2种不同的配位模式,是含六核簇合物单元的二维网络结构。

2-Picolinic acid(2-PA) has been integrated with Keggin-type [SiW12O40]4- and [PMo12O40]3- polyoxometa-lates units to achieve final products: H2[(CH3)4N]6[Cu(2-PA)2(SiW12O40)2](1) and(H3O)[Cu6(2-PA)9(PMo12O40)(NO3)](2). These two inorganic-organic hybrid compounds have been characterized by single-crystal X-ray diffraction,infrared spectroscopy and powder X-ray diffraction. Compound1 crystalizes in monoclinic system with space group P21/c, and the asymmetric unit is composed of one Cu(Ⅱ) ion, two 2-PA ligands and two [SiW12O40]4-Keggin-type polyoxometalate anions. Compound1 is a zero-dimensional structure. The cyclic voltammogram of1-CPE(the bulk-modified carbon paste electrode) showed that the half-wave potentials(E1/2=(Ecp+Eap)/2) of Ⅰ-Ⅰ′, Ⅱ-Ⅱ′ and Ⅲ-Ⅲ′were-270,-516 and-708 mV, respectively, when the sweep speed was 100 mV·s-1. Compound2 crystallizes in trigonal system with space group R3 c, there are two crystallographically independent Cu ions with two kinds of coor-dination modes in2 and it is a two-dimensional networks containing hexanuclear clusters. CCDC: 1978845,1;1978846,2.