Two heterotrimetallic organic frameworks constructed using a functionalized Schiff base ligand: syntheses, structures and visible photocatalytic activities for the degradation of chlorophenols

Abstract

Two heterotrimetallic organic frameworks [(CH₃)₂NH₂][Cd₂Na(Fe-L)₂(H₂O)₆]·4DMF·4H₂O (1) and [ZnNa(Fe-L)(H₂O)]·2DMF·2H₂O (2), have been synthesized via the reaction of a novel tetracarboxyl-functionalized 1,2-ethanediamino-N,N′-bis(3-tertiarybutyl-5-((3,5-carboxybenzyl)oxy)salicylidene) (H₆L) Schiff base ligand. In 1 and 2, the internal [N₂O₂] pockets of L⁶⁻ anions are embedded by Fe(III) ions, while the external carboxylate groups are ligated by Zn(II)/Cd(II) and Na(I) ions. Both frameworks display fascinating 3D frameworks. The photodegradation properties of 1 and 2 towards 4-chlorophenol (4-CP) and 2,4-dichlorophenol (2,4-DCP) under visible light have been systematically investigated. Their magnetic behaviors have also been studied.