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

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)/NiFe 2 O 4 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 Tl 3+ demonstrated high effectiveness and reliability in detecting Tl 3+ 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 Tl 3+ , 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 −1 cm −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 cm 2 . 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 Tl 3+ ion sensor's performance was validated by analyzing real environmental samples, and satisfactory results were obtained.