Abstract
In this study, we report a novel ternary conductive hybrid material with high stability, conductivity, and excellent electrochemical Ga3+ sensing ability. Ternary poly(pyrrole-co-o-toluidine)/CoFe2O4/reduced graphene oxide-oxidized single-wall carbon nanotube nanocomposites in the form of P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs have been synthesized through an in situ chemical polymerization method via a facile three-step approach. Single phase CoFe2O4 (CF) nanoparticles (NPs) were synthesized using an egg white method, while reduced graphene oxide-oxidized single-wall carbon nanotubes R(GO-OXSWCNTs) were prepared via co-reduction of graphene oxide along with oxidized SWCNTs flowed by coating CF and R(GO-OXSWCNTs) with a poly(pyrrole-co-o-toluidine) matrix P(Py-co-OT) copolymer. The results of X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR) and Raman indicated that the P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs were effectively synthesized with strong interactions among the constituents. The thermal stability of P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs is considerably enhanced in the composite format. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) demonstrated that CF and R(GO-OXSWCNTs) were well coated by P(Py-co-OT). The electrical conductivity study showed that P(Py-co-OT) and R(GO-OXSWCNTs) might significantly improve the conductivity and the electrochemical performance of the CF. A Ga3+ ion selective electrochemical sensor was fabricated by coating a glassy carbon electrode (GCE) with synthesized P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs by using 5% Nafion binder. The slope of the calibration curve was used to calculate the sensor's analytical parameters, such as sensitivity (13.0569 mu A mu M-1 cm(-2)), detection limit (96.27 +/- 4.81 pM), quantification limit (43.523 pM), response time, reproducibility, large linear dynamic range, and linearity. The validation of the P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs/GCE sensor probe was investigated by a standard addition method (recovery) in the presence of various environmental samples and satisfying results were obtained.