Core–shell- shell structured P(Ani-co-Py)/NiF-grafted-(Go-PPD)-PPy nanocomposites prepared via two steps polymerization of conducting polymer for sensitive Tl3+detection

Abstract

In this research, a newly developed structure consisting of a shell made of (Graphene oxide-Paraphenylenediamine)/Polypyrrole (Go-PPD)-PPy was successfully synthesized on a binary poly(aniline-co-o-pyrrole)/NiFe2O4 core-shell nanocomposite, known as P(Ani-co-Py)/NiF NCs. The synthesis process involved a two-step approach, starting with the in-situ oxidative polymerization of the copolymer P(Ani-co-Py) on NiF nanoparticles (NPs). This was followed by a subsequent in-situ oxidative polymerization of (Go-PPD)-PPy on the P(Ani-co-Py)/NiF core-shell NCs, resulting in the formation of PPy-(Go-PPD)/P(Ani-co-Py)/NiF NCs with a core-shell-shell structure. In this method, the developed sensor designed specifically for Tl3+ demonstrated high effectiveness and reliability in detecting Tl3+ ions within a phosphate buffer medium. During the fabrication process of the sensor probe, the stability of the synthesized PPy-(Go-PPD)/P(Ani-co-Py)/NiF NCs on a glassy carbon electrode (GCE) was enhanced significantly by incorporating nafion, a 5% suspension in ethanol. A calibration curve was established by drawing the current toward the concentration of Tl3+, showing a linear relationship. By looking at the maximum linear portion of the calibration curve, a linear dynamic range of 0.1 nM to 0.01 mM was determined. Sensor sensitivity has been calculated as 1.06 µAµM−1cm−2, by setting the slope of the calibration curve and GCE (the surface area of the glassy carbon electrode), which was measured as 0.0316 cm2. The lower limit of detection (LOD) was determined to be 92.09±4.60 pM based on a signal-to-noise ratio of 3. Limit of quantification (LOQ) is calculated as 279.06 pM from 10*(LOD)/3.3. Finally, the proposed Tl3+ ion sensor's performance was validated by analyzing real environmental samples, and satisfactory results were obtained.