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 [HPMo 12 O 40 ] ( 1 ), {[Cu(bipy)] 4 [GeW 12 O 40 ]}·H 2 O ( 2 ), and {[Cu(bipy)] 4 [Mo 15 O 47 ]}·2H 2 O ( 3 ) (bipy = 4,4′-bipyridine), have been hydrothermally synthesized and characterized by routine physical methods. Compound 1 exhibits 1D 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 1D 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.