One-pot synthesis of Fe 3 O 4 /polypyrrole/graphene oxide nanocomposites for electrochemical sensing of hydrazine

The authors describe the synthesis of a nanocomposite consisting of Fe 3 O 4 nanoparticles, polypyrrole and graphene oxide (Fe 3 O 4 /PPy/GO), and its application to voltammetric sensing of hydrazine. The nanocomposite can be synthesized by combining chemical oxidative polymerization and co-precipitation. Fe(III) ion is employed as both the oxidant for pyrrole and as a precursor of Fe 3 O 4 . The nanocomposite was characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). TEM observations revealed that large numbers of Fe 3 O 4 are homogeneously and densely distributed. The Fe 3 O 4 /PPy/GO composite was placed in a glassy carbon electrode, and the resulting sensor, best operated at around 0.2 V (vs. SCE) exhibited excellent response to dissolved hydrazine over the 5.0 μM to 1.3 mM concentration range, a sensitivity of 449.7 μA mM −1 cm −2 and a low detection limit of 1.4 μM (at an S/N ratio of 3). Graphical abstract Fe 3 O 4 /polypyrrole/graphene oxide nanocomposites were synthesized through one-pot process and then the nanocomposites were used for fabricating a nonenzymatic sensor for hydrazine.