Efficient photocatalytic degradation of methyl violet using two new 3D MOFs directed by different carboxylate spacers

Two highly stable metal–organic frameworks (MOFs) assembled by a flexible 1,4-bis(2-methylimidazol-1-yl)butane (bib), and two different aromatic carboxylate coligands, namely, [Zn(BDC–OH₂)(bib)] (1) and [Cd₃(BTC)₂(bib)(DMF)₃] (2) (H₂BDC–OH₂ = 2,5-dihydroxyterephthalic acid, H₃BTC = 1,3,5-benzenetribenzoic acid), were designed and synthesized. 1 showed a 4-fold interpenetration of 4-connected dia-type topological net. In 2, the 3D topological structure can be viewed as a (3,4,5)-connected network, and its Schläli point is {4·6²}₂ {4²·6·8³} {4⁶·8⁹}. Different auxiliary carboxylate ligands were examined with respect to the building of various structures. 1 and 2 have outstanding photocatalytic behaviors for the disintegration of methyl violet (MV) under UV irradiation.