Construction of POMOFs with different degrees of interpenetration and the same topology

Abstract

Three metal–organic networks with different degrees of interpenetration based on Keggin-type polyoxometalates have been hydrothermally synthesized by a simple change in the organic ligand and structurally characterized. By changing the length and the coordination mode of the ligand, we obtained compound 1 which represents the first example of a three-fold interpenetrated POMOF architecture with pcu topology, and POMs occupy the vertex of the pcu lattice. Compound 2 exhibits a POM-pillared metal–organic framework, which can be described overall as a two-fold interpenetrated pcu framework, and POMs occupy the arris of the pcu lattice. Different from 1 and 2, compound 3 can be described as a single pcu network and POMs occupy the face of the pcu lattice. The influence of the organic ligand on the degree of interpenetration is also discussed. Furthermore, the results indicate that the three compounds present good photocatalytic activities.