Hydrothermal Synthesis, Structures and Properties of Two Silver-Containing Organic–Inorganic Hybrids Based on Precursor [AlW12O40]5−

Abstract

Two new silver-containing inorganic–organic hybrid compounds [Ag(2-MMIZ)2]6{[Ag(2-MMIZ)2]2[Ag(2-MMIZ)]2[AlW12O40]2} (1) and [Ag(2-MMIZ)2]5[AlW12O40] (2) based on Keggin polyoxometalates and Ag complex have been successfully synthesized by reaction of AgNO3, 2-MMIZ (2-methylimidazole), and the α-Na5[AlW12O40]·13H2O precursor under hydrothermal conditions, and these two compounds were well characterized by elemental analyses, IR spectrum, UV–Vis spectrum, Thermogravimetric analyses, Powder X-ray diffraction measurements and single-crystal X-ray diffraction. The structure of Compound 1 represents the first dimer anion {[Ag(2-MMIZ)2]2[Ag(2-MMIZ)]2[AlW12O40]2}6− and six free [Ag(2-MMIZ)2]+ segments as cations, among the five crystallographically independent of [Ag(2-MMIZ)] segments in 1, Ag atoms exist three types of coordination configurations including linear, triangular and T type. Compound 2 is composed of one α-Keggin polyoxoanion [AlW12O40]5− and five free [Ag(2-MMIZ)2]+ segments as cations, there is only a linear coordination mode of Ag atoms in 2. Compounds 1 and 2 show photocatalytic activity for degradation of organic dye Rhodamine-B. The first dimmer anion {[Ag(2-MMIZ)2]2[Ag(2-MMIZ)]2[AlW12O40]2}6− based on [Ag(2-MMIZ)]+ cations, [Ag(2-MMIZ)2]+ cations and [AlW12O40]5− polyoxoanions can be used for degradation of organic dye Rhodamine-B.