Unprecedented metal-ion metathesis in a metal–carboxylate chain-based metal–organic framework

Abstract

A new three-dimensional (3D) metal–organic framework (MOF), [Zn₃L₂(DMF)₂]·2DMF (1-Zn), was prepared by the reaction of 5-(4-carboxybenzoylamino)-isophthalic acid (H₃L) with Zn(NO₃)₂·6H₂O under solvothermal conditions. Interestingly, the zinc ions in the zinc–carboxylate chains of complex 1-Zn could be exchanged with copper ions via direct single-crystal to single-crystal transformation (SC-SC). The complete and irreversible exchange of the metal ions from Zn²⁺ to Cu²⁺ and retention of the framework structure were verified by powder X-ray diffraction (PXRD), ICP-AES and SEM-EDS. Solid state photoluminescence measurements showed metal-specific properties.