The synthesis and characterization of the 3-D framework of SO42− supported Keplerate-type polyoxometalate

Abstract We report a Keplerate-type polyoxometalate Na 18 K 8 [{Mo 6 O 21 (H 2 O) 3 (SO 4 )} 12 (Fe(H 2 O) 2 ) 30 ]·ca. 67 H 2 O ( 1 ), which is composed of 12 pentagonal {(Mo)Mo 5 } units and 30 [Fe(H 2 O) 2 ] 3+ linkers. This giant heterometal Keplerate-type cluster is supported by SO 4 2− and display interesting topologies, which are connected by two kinds of Na + cations (mononuclear and binuclear Na + cations) to form three-dimensional (3-D) open-framework. The compound was characterized by the elemental analysis, thermogravimetry, spectroscopic methods (IR and UV/Vis), bond valence sum (BVS) calculations, X-ray photoelectron spectroscopy (XPS) and single crystal X-ray structure analysis. The photocatalytic property of compound 1 has been investigated, which shows a good photocatalyst for the degradation of RhB.