Greener and facile synthesis of hybrid nanocomposite for ultrasensitive iron (II) detection using carbon sensor

Abstract

Novel hybrid nanocomposite has been developed using an environmentally friendly method. The new hybrid nanocomposite was synthesized in two green steps at ambient conditions as graphite decorated with gold nanoparticles and then coated with polypyrrole chains through solvent-less vapor polymerization method. Developed graphite-gold nanoparticles-polypyrrole (GR-AuNP-PPY) nanocomposite has been explored as an effective electroactive material for preparing iron (II) ion-selective carbon paste electrode. The developed nanocomposite mass loadings in the fabricated carbon sensor were varied from 12 to 72 mg. The electrode incorporating 56 mg of GR-AuNP-PPY exhibited an excellent bivalent Nernstian slope value of 30.0 +/- 0.23 mV decade(-1) over a perceptible spacious concentration range of 1.0 x 10(-6) - 1.0 x 10(-2) mol L-1 within pH range from 2.5 to 5.5 displaying a fast response time of 3 s. The proposed GR-AuNP-PPY based sensor revealed a good discriminating power of iron (II) ion over numerous metal ions. The analytical applicability of the GR-AuNP-PPY based electrode has been investigated for the quantitative detection of iron (II) ion in spiked water samples using the calibration curve method. The aforementioned sensor displayed excellent selectivity, good response time, high accuracy and precision. Additionally, the mechanism of electroactive material interaction with iron (II) was investigated and found to be an ion imprinting like mechanism.