Two multifunctional organic-inorganic hybrid complexes based on polyoxometalates, BiEDTA and sodium linker: crystal structures, photochromic, and catalytic performances

Two 3-D organic–inorganic hybrid supermolecular complexes, Na(BiHEDTA·2H 2 O) 3 (PW 12 O 40 )·2H 3 O ( BiPW ) and Na(BiHEDTA·2H 2 O) 3 (PMo 12 O 40 )·2H 3 O·2H 2 O ( BiPMo ) ethylenediamine tetraacetic acid (EDTA) have been synthesized by solution method and characterized by ultraviolet visible (UV–vis) spectroscopy, thermogravimetric-differential thermal analysis, photoluminescence, cyclic voltammetry, and single-crystal X-ray diffraction (XRD).

XRD analysis reveals that BiPW and BiPMo are isostructural with 3-D architectures assembled by 2-D layer tetranuclear cation and a Keggin-type polyoxoanion. Although these two hybrids exhibit similar structures, the properties depend on the nature of polyoxoanion [PM 12 O 40 ] 3− ( M = W , Mo). Under UV irradiation, BiPW and BiPMo show fast response of reversible and irreversible photochromism, respectively.