Effective Azo-functionalized metal-organic framework colorimetric and ratiometric sensor for detection of heavy metals in aqueous solution by the naked eye

Abstract

In this work, azo-functionalized zirconium metal organic framework grafted on carboxymethlated cellulose membrane (UiO-66-Azo-Im@CCM) was synthesized by solvothermal method. The developed sensor was systematically characterized and their sensitivity, selectivity and ratiometric properties were investigated. The effect of pH on the sensing performance of the fabricated sensor was also studied. The findings show that developed sensor exhibited excellent sensitivity, selectivity and ratiometric property toward copper, cobalt and nickel heavy metal ions. The calculated limit of detection (LOD) these heavy metals ions were lower than the world health organization permissible concentration that reveals its potential candidacy in monitoring these heavy metals. This work confirms that the developed UiO-66-Azo-Im@CCM can used as powerful tool for the monitoring of Cu2+, Ni2+, and Co2+ without need of the sophisticated instrument. Therefore, we anticipate that it will play its role in environmental remediation in general wastewater treatment in particular.