Keggin型多酸基超分子化合物H3[{H(4-AP)}6(PMoⅤ6MoⅥ6O40)]的结构和电催化性能

通过水热合成方法,以钼酸铵、氯化镍和4-氨基吡啶为原料成功合成了一个Keggin型多酸基超分子化合物H₃{H(4-AP)}₆(PMo^V₆Mo^VI₆O₄₀)] (4-AP=4-氨基吡啶)。该化合物的结构单元包含一个PMo^V₆Mo^VI₆O₄₀]^9-阴离子和6个质子化的配体。而PMo^V₆Mo^VI₆O₄₀]^9-阴离子与配体之间通过N(1)—H(1)…O(3)、N(2)—H(2A)…O(5)和N(2)—H(2B)…O(1)三种氢键相互作用,进而形成二维超分子层。通过X射线单晶衍射、IR和粉末X射线衍射对其进行表征。晶体结构分析表明:该标题化合物属于三方晶系,R-3空间群,a=2.191 2 (10) nm, b=2.191 2 (10) nm, c=1.042 3(5) nm, α=β=90°, γ=120°, V=4.333 8(4) nm³, Z=3, R₁=0.036 2, wR₂=0.095 6, 电催化性质研究表明该标题化合物对H₂O₂和K₂Cr₂O₇具有良好的电催化还原效果,以及对抗坏血酸具有良好的电催化氧化效果。

Structure and Electrocatalytic Performance of a Keggin-Type Polyoxometalate-Based Supramolecular Complex H3[{H(4-AP)}6(PMoV6MoVI6O40)]

A Keggin-type polyoxometalate-based supramolecular complex H₃{H(4-AP)}₆(PMo^V₆Mo^VI₆O₄₀)] (4-AP=4-aminopyridine) was successfully synthesized from ammonium molybdate, nickel chloride, and 4-aminopyridine by hydrothermal method. The structural unit of the complex contains a PMo^V₆Mo^VI₆O₄₀]^9- anion and six protonated ligands. PMo^V₆Mo^VI₆O₄₀]^9- anion and ligands are connected to each other by N(1)—H(1)…O(3), N(2)—H(2A)…O(5), and N(2)—H(2B)…O(1) hydrogen bonds, which further form a two-dimensional supramolecular layer. It was characterized by X-ray single crystal diffraction, IR spectra, and powder X-ray diffraction. The crystal structure analysis shows that the complex belongs to the trigonal crystal system, R-3 space group, a=2.191 2 (10) nm, b=2.191 2 (10) nm, c=1.042 3 (5) nm, α=β=90°, γ=120°, V=4.333 8 (4) nm³, Z=3, R₁=0.036 2, wR₂=0.095 6. The electrocatalytic performance shows that the complex has a good electrocatalytic reduction effect on H₂O₂ and K₂Cr₂O₇. It also has a good effect of electrocatalytic oxidation on ascorbic acid.