Electrochemical Sensor for Detection of p-nitrophenolBased on Nickel Oxide Nanoparticles/α-cyclodextrin Functionalized Reduced Graphene Oxide

p-Nitrophenol (p-NP) is a high priority toxic pollutant and that has harmful effects on human, animals and plants. Thus, the detection and determination of p-NP present in the environment is an urgent as well as highly important requisite. The present article, therefore focused on the construction of a novel electrochemical sensor based on NiO nanoparticles/alpha-cyclodextrin functionalized reduced graphene oxide modified glassy carbon electrode (NiO-NPs-alpha-CD-rGO-GCE) for the selective and sensitive detection of p-NP. UV-vis, high resolution transmission electron microscopy (HR-TEM), selected area electron diffraction pattern (SAED) and X-ray diffraction (XRD) analysis confirms the formation of highly pure NiO nanoparticles. Field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), and cyclic voltammetry (CV) were used to characterize the step-wise electrode modification process. DPV was carried out to quantify p-NP within the concentration range of 1-10 mu M and found the detection limit of 0.12 nM on the basis of the signal-to-noise ratio S/N=3. The electrode can able to detect different isomers of nitrophenols. Interferences of other pollutants such as phenol, p-aminophenol, o- and m- nitrophenol, 4-chlorophenol, 2,6-dichlorophenol and ions like K+, Cd2+, Cl-, SO42- did not affect the sensing of p-NP. The newly developed sensor exhibited diffusion controlled kinetics and had excellent sensitivity, selectivity and reproducibility for the detection of p-NP. The electrode showed good recoveries in real sample analysis.