Core-shell-shell nanocomposites structured polyaniline-rGO coated copolymer of NiFe2O4@poly(aniline-co-pyrrole) for sensitive Co2+ detection

Abstract

A two-step in situ chemical polymerization approach that involved the simple in-situ oxidative polymerization of (ANI-co-Py) as a copolymer on NF nanoparticle NPs, followed by the succeeding in-situ oxidative polymerization of ANI-rGO on the P(ANI-co-Py)/NF core–shell structure, has successfully obtained a shell of polyaniline (PANI)- reduced graphene oxide (rGO) on poly(aniline-co-pyrrole)/NiFe2O4/P(ANI-co-Py)/NF core–shell. The resulting PANI-rGO/P(ANI-co-Py)/NF NCs consist of NiFe2O4 nanoparticles that acted as the “core” surrounding conducting copolymers, while the intermediate rGO serves as the bridge network connecting the copolymer and PANI, offering good structural stability as well as an effective electron transfer pathway. Moreover, the produced nanocomposite NCs also exhibit the core shell-shell structure with the features of electrode materials. A reliable sensor selective to Co2+ ion has been developed based on the high structural and compositional properties of the as-obtained PANI-rGO/P(ANI-co-Py)/NF NCs. Where a glassy carbon electrode (GCE) was coated by a slurry of synthesized PANI-rGO/P(ANI-co-Py)/NF NCs, which was stabilized using a suspension of Nafion (5 % suspension in ethanol) as a binding agent. A calibration curve of the current data and the corresponding concentrations of Co2+ ions have been established. From the calibration curve, the reliability of the linear dynamic range (0.1 nM–0.01 mM), the sensor sensitivity (204.2658 µA.µM−1.cm−2), and the lower limit of detection (99.27 ± 4.96 pM) have evaluated. Finally, the designed sensor was subjected to examining real environmental samples, where the fabricated sensor exhibited a successful high reproducibility. Recently, the development of sensors based on nanocomposites of organometallic on GCE has become key in the field of sensor development. The simple rapid synthesis of the PANI-rGO/P(ANI-co-Py)/NF NCs sensor will considerably contribute to the field of sensor management. In addition, the good performance of the PANI-rGO/P(ANI-co-Py)/NF NCs electrodes has drawn attention to them as promising electrode materials for high-performance sensors.