Cu decorated multiwalled carbon nanotubes: Application to electrocatalytic oxidation and determination of 4-nitrophenol in river water samples by square-wave voltammetry

A simple and fast electrochemical method was described and evaluated for the determination of hazardous compound, 4-nitrophenol. In this work, trace amounts of 4- nitrophenol were determined by square – wave voltammetry. A glassy carbon electrode was modified with multi-walled carbon nanotubes and copper nanoparticles. A synergistic effect was observed between Cu nanoparticles and carbon nanotubes which resulted in enhanced oxidation peak current of 4-nitrophenol. The modified electrode showed more sensitivity towards 4-nitrophenol compared to unmodified one. A wide linear concentration range from 0.2 to 298.0 μM was obtained for 4-nitrophenol with a detection limit of 0.06 μM. Reproducibility and repeatability of the method were evaluated for determination of 4-nitrophenol (0.1 mM) as 3.47% and 2.30%, respectively (relative standard deviation, RSD %), which are acceptable. The method was applied to the analysis of 4- nitrophenol (22.2 μM) in spiked river water samples, successfully. Simplicity, sensitivity, selectivity and high efficiency of the proposed method can be used in routine analysis of trace amounts of 4-nitrophenol in polluted waters.