Sensitive and selective sensor for monitoring of ۴- nitrophenol levels in environmental water samples based on Poly (Biphenol / biphenoquinone - vanadium (IV)) modified electrode

In the present work, we report a new method for facile and effective synthesis of poly(biphenol/biphenoquinone-vanadium (IV)) (poly BP/BQ-VIV) for the first time. The poly BP/BQ-VIV wasapplied for modification of a carbon past electrode (CPE/ poly BP/BQ-VIV) to enhance the electro-catalyticactivity towards electro-oxidation of ۴-nitrophenol (۴-NP) molecules in solutions. The structure and theproperties of the synthesized poly BP/BQ-VIV were characterized by various techniques such as FESEM, TEM,EDX, FT-IR, UV-Vis, XPS analysis, cyclic voltammetry, differential pulse voltammetry and electrochemicalimpedance spectroscopy. The CPE/ poly BP/BQ-VIV electrochemical sensor, exhibits a well-defined anodicpeak for ۴-NP molecules at ۱.۱۸ V vs. Ag/AgCl reference electrode. Under optimum experimental conditions,the CPE/ poly BP/BQ-VIV electrochemical sensor, shows a low detection limit of ۶۰ nM, current sensitivity of۰.۹۹۶ μA μM-۱ and a linear response in the concentration range of ۰.۰۵ to ۲۰۰ μM for quantitativemeasurement of ۴-NP in aqueous solutions. The results verify that the CPE/ poly BP/BQ-VIV presents excellentreproducibility, appreciable repeatability, satisfactory stability, and high selectivity for detecting of ۴-NP intap and river water samples