Determination of 4-nitrophenol in water by use of a screen-printed carbon electrode modified with chitosan-crafted ZnO nanoneedles.

The toxicity and environmental pollution by nitro aromatic compounds in water samples is the most recognized problem in worldwide. Hence, we have developed a simple and highly sensitive electrochemical method for the determination of 4-nitrophenol (4-NP) in water samples based on a chitosan (CHT) crafted zinc oxide nanoneedles (ZnO NDs) modified screen printed carbon electrode. The CHT/ZnO NDs were characterized by Field emission scanning electron microscope, Fourier transform infrared spectroscopy and X-ray diffraction technique. The CHT/ZnO NDs modified electrode showed an enhanced electrocatalytic activity and lower potential detection towards 4-NP, compared with other modified electrodes. Under optimum conditions, the differential pulse voltammetry (DPV) response of CHT/ZnO NDs modified electrode displayed a wide linear response range from 0.5 to 400.6μM towards the detection of 4-NP with a detection limit (LOD) of 0.23μM. The CHT/ZnO NDs modified electrode was used for specific and sensitive detection of 4-NP in presence of possible interfering species and common metal ions with long-term stability. In addition, the excellent analytical performance of the proposed sensor was successfully applied for determination of 4-NP in water samples.