Metal-Organic Frameworks-Based Sensors for Detection of Toxic Environmental Contaminants

Abstract

Continuous industrialization has led to the release of many heavy-metal pollutants from industrial wastes into the natural environment. In the recent decade, there is an increasing demand for accurate environmental pollution monitoring and control requires new sensing techniques with high sensitivity, selectivity, and reliability. Metal−organic frameworks (MOFs) have received considerable attention for environmental contaminant detection including anions, heavy metal ions, volatile organic compounds, and toxic gases because of their high surface area, porosity, large pore volumes, tunable structures, and open metal sites. A Fe3+ ion-selective electrochemical sensor was fabricated by depositing the synthesized Cu(TBC)-MOF on a glassy carbon electrode (GCE) and the electrochemical method was investigated in detail in an aqueous medium. The proposed Fe3+ ion sensor exhibited a linear relationship for current vs. Fe3+ ion concentration in the concentration range of 0.001 M to 100 M. The limit of detection value was found to be 0.52 μM in aqueous media which is lower than the acceptable value of iron in drinking water (0.3 mg/L). The presence of other ions such as Na+, K+, Mg2+, Pb2+, Zn2+, Cd2+, Cl-, NO -, and SO 2- 3 4 did not interfere with the detection of Fe3+ ions.