A highly selective carbon paste electrode enhanced by Cu‐encapsulated poly(amidoamine) for the simultaneous detection of organic and inorganic contaminants

Abstract

AbstractIn this study, a copper/poly(amidoamine)/multi‐walled carbon nanotube/reduced graphene oxide (Cu/PAMAM/MWCNT/rGO) complex was synthesized for fabricating an electrochemical sensor to simultaneously detect nitrate and nitrite ions as inorganic contaminants, and 4‐chlorophenol (4‐CP) and 1,2,5,8 tetrahydroxy anthraquinone (THA) as organic pollutants. The prepared Cu/PAMAM/MWCNT/rGO electrode was characterized using scanning electron microscopy (SEM), Fourier‐transform infrared (FT‐IR), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS). Cyclic voltammetry (CV) was performed to investigate the influence of the pH of the solution, concentration of anions, and scan rate on the analytical performance of the electrodes. The simultaneous determination of nitrite/nitrate ions using a Cu/PAMAM/MWCNT/rGO electrode showed sensitivities of 8.030 × 10−3 and 5.370 × 10−3 μA μM−1 mm−2, and limits of detection (LODs) of 0.081 and 0.115 μM, respectively. For the simultaneous determination of 4‐CP/THA, the sensitivities of the modified electrode were 0.0105 and 9.399 × 10−3 μA μM−1 mm−2, and detection limits were 0.062 and 0.070 μM respectively.