Zinc metal–organic framework with 3-pyridinecarboxaldehyde and trimesic acid as co-ligands for selective detection of Cr (VI) ions in aqueous solution

Abstract

There is an increasing need for the development of probes for the detection of hexavalent chromium since it is a known carcinogen, which can cause adverse effects on human health. Metal-organic frameworks (MOFs) have shown successful detection and removal of hazardous substances from aqueous media. This work presents the use of simple organic ligands such as 3-pyridinecarboxaldehyde and trimesic acid with Zn(II) ion to fabricate a new MOF that exhibits sensitive and selective luminescence quenching response towards CrO4 2− and Cr2O7 2− species in aqueous solution. The MOF showed a detection limit of 0.67 μM (0.078 ppm) as CrO4 2− species and 1.91 μM (0.41 ppm) as Cr2O7 2− species. Results reveal that the as-synthesized MOF could serve as a good luminescent sensor for CrO4 2− and Cr2O7 2− species in the contaminated aqueous phase.