Engineering the heterogeneous photocatalytic activity of crystalline decatungstate-based coordination polymers

Decatungstate (W 10 O 32 4− , DT) is a metastable polyoxometalate anion which presents excellent photocatalytic ability. In order to stabilize the DT species, four decatungstate-based coordination polymer compounds with different DT coordination modes, namely [Cu 2 (3-bpo) 2 (H 2 O) 2 (DMSO) 2 ][W 10 O 32 ]·14H 2 O ( 1 ), [Cu 2 (3-bpo) 2 (DMSO) 4 ][W 10 O 32 ] ( 2 ), [Cu 2 (4,4′-bipy) 4 ][H 2 W 10 O 32 ] ( 3 ) and [Cu(4,4′-bipy) 3 (DMSO)(H 2 O)][TBA][HW 10 O 32 ]·H 2 O ( 4 ) (DMSO = dimethyl sulfoxide, 3-bpo = 2,5-bis(3-pyridyl)-1,3,4-oxadiazole, 4,4′-bipy = 4,4′-bipyridine, TBA = tetrabutylammonium) were synthesized under controlled solvothermal conditions in the mixed solvent of DMSO and H 2 O. The heterogeneous photocatalytic activity of these four compounds in the degradation of rhodamine B was tested and the results show that they possess fairly high photocatalytic activity without leaching of DT during the reaction. The effect of the coordination modes of terminal oxygen (O t ) atoms in DT anions on the activity was investigated. Four novel decatungstate-based coordination polymers were constructed, exhibiting differentiated catalytic activities due to their distinct decatungstate coordination modes.