A Zn based two-dimensional metal-organic framework as a dual ion sensor in aqueous media.

Abstract

Excess and shortage of some metal ions like Fe3+ ions in drinking water away from permissible levels can cause severe health threat. Similarly, chromium is found chiefly in a hexavalent form that also poses a threat to human health. Human beings and other living organisms are at greater risk of exposure to these toxic ions and other chemicals. Development of new, effective and fast sensors is the need of time. MOFs are nanoporous materials which have quite fast detection time and effective in sensing of various metal ions and hazardous chemicals. A Zn based two-dimensional is synthesized and applied for the sensing of Fe3+ and Cr2O72- ions. Due to the presence of free oxygen and nitrogen atoms, this MOF showed quite high sensitivity with Ksv value of 1.8×104 and 6.5×104 with a limit of detection (LOD) 2.5μM and 0.15μM for Fe3+ and Cr2O72-ions respectively. This study proved the two-dimensional MOF as excellent sensor for the detection of Fe3+ and Cr2O72- ions. This can be used as colorimetric sensor for these ions due to color changes visible to the naked eye.