Two three-dimensional porous frameworks built from metal-organic coordination polymer sheets pillared by polyoxometalate clusters.
Two new porous frameworks [Ni(bix)2][VW12O40]·(H2bix)·H2O (1) and [Co(bix)2][VW12O40]·(H2bix)·2H2O (2) (bix = 1,4-bis(imidazol-1-ylmethyl)-benzene) composed of Keggin polyoxometalates (POMs) and metal-organic coordination polymer sheets have been successfully obtained, and characterized by elemental analysis, IR spectra, thermal gravimetric analysis, and single crystal X-ray diffraction. Structural analysis reveals that the 2D metal-organic coordination polymer sheets in the two compounds are constructed from the transition-metal (TM) cations and the flexible N-donor ligand bix, which are further pillared by POM clusters into the 3D porous frameworks. Powder X-ray diffraction (PXRD) patterns of 1 indicate the structural integrity of the framework in aqueous solution with a wide pH range of 1 to 11, and in common organic solvents (methanol, ethanol and DMF). Photocatalytic studies indicate that compounds 1 and 2 are not only active photocatalysts for degradation of rhodamine B (RB), but very stable and easily separated from the photocatalytic system for reuse as well.
Key Laboratory of Polyoxometalate Science of Ministry of Education, Department of Chemistry, Northeast Normal University, Renmin Street No. 5268, Changchun, Jilin 130024, P. R. China. zhangzm178@nenu.edu.cn wangeb889@nenu.edu.cn.
Qing
Q
Lan
Jun
J
Zhang
Zhi-Ming
ZM
Zhang
Ying
Y
Lu
En-Bo
EB
Wang