Rapid impedimetric detection of cadmium ions using Nanocellulose/ligand/nanocomposite (CNT/Co3O4)

Abstract

In this work, a new class of heterocyclic-ligands/Nanocellulose/Co3O4/carbon-nanotube-nanocomposite was synthesized, characterized, and implemented as a new sensor platform for the ultra-trace impedimetric direct detection of cadmium ions in tap water samples. A simple synthesis approach was used for producing cellulosic nanostructures that were integrated with several heterocyclic ligands (L/Nanocellulose) to be exploited as the sensor platform. For acquiring high electrocatalytic combined with fast electrochemical responses, metal oxides/carbon nanotubes were integrated with one of the selected L/Nanocellulose to eventually form CNT/Co3O4/L/cellulose nanocomposite. The impedimetric method was optimized to reach sub-picomolar sensitivity with no cross-reactivity with other metal ions. From the calibration curve, high sensitivity and a wide linear range was achieved over the concentrations (10-13 M to10-2 M), with lower of detection limit (LOD) of 1.5 × 10-13 M (S/N = 7), R2 of 0.99. The sensor was applied for real sample (tap-water) analysis, while a high recovery percentage (96–120 %) was attained.