Electrochemical molecularly imprinted polymer based on zinc oxide/graphene/poly(o-phenylenediamine) for 4-chlorophenol detection

An electrochemical sensor on a modified glassy carbon electrode (GCE) for the detection of 4-chlorophenol (4-CP) was investigated. A GCE was coated by a zinc oxide nanoparticle/graphene nanoplatelet/poly(o-phenylenediamine) polymer nanocomposite (GCE/ZnO/GNPs/MIP). The nanocomposite improved the electrochemical response and sensitivity of the sensor for the detection of 4-CP. The surface morphology and crystal structure of the prepared nanomaterial were characterized using different chemical and physical techniques, showing homogenous distributions of ZnO and GNPs over the electrode. The electrochemical behavior of the GCE/ZnO/GNPs/MIP nanocomposite-based sensor was evaluated using cyclic voltammetry and electrochemical impedance spectroscopy. Under optimized experimental conditions, the electrochemical sensor exhibited excellent analytical performance with a very low detection limit. The electrochemical sensor was utilized to determine 4-CP levels in real water samples; the sensor exhibited high selectivity, sensitivity, and repeatability. These results showed that the GCE/ZnO/GNPs/MIP sensor could be a facile, robust, practical, low-cost and rapid tool for potential on-line monitoring of 4-CP in water.