Assembly of Multiply Chain-Modified Polyoxometalates: From One-to Three-Dimensional and from Finite to Infinite Track

By employing the polyoxometalates (POMs) with different sizes as structural motifs, three new organic-inorganic hybrids based on the multiply Cu-bipy coordination polymeric chain-modified POMs, [Cu(bipy)](2)[HPMo12O40] (1), {[Cu(bipy)](4)-[GeW12O40]}center dot H2O (2), and {[Cu(bipy)](4)-[GeW15O47]}center dot H2O (3) (bipy = 4,4'-bipyridine), have been hydrothermally synthesized and characterized by routine physical methods. Compound I exhibits ID chain in which Keggin POMs are modified by bitrack Cu-bipy chains. Compound 2 represents a 2D layer of tetra-track Cu-bipy chain modified Keggin POMs. And compound 3 shows an infinite-track Cu-bipy chain-modified molybdenum oxides 3D structure, namely, a modifying state of high point. Because the differences of POMs affect the structures of the hybrids-the number of Cu-bipy chains from bi- to infinite-track, and the dimension from ID to 3D-their successful isolation demonstrates that members of the vast family of POMs may be employed as structural motifs in designing more solid-state materials. Additionally, their electrochemical properties have been studied.