Magnetite Nanorods Stabilized by Polyaniline/Reduced Graphene Oxide as a Sensing Platform for Selective and Sensitive Non-enzymatic Hydrogen Peroxide Detection

In this study, magnetite nanorods stabilized on polyaniline/reduced graphene oxide (Fe₃O₄@PANI/rGO) was synthesized via a wet-reflux strategy. The possible formation of Fe₃O₄@PANI/rGO was morphologically and structurally verified by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Furthermore, the thermal stability of Fe₃O₄@PANI/rGO was measured by a thermogravimetric analyzer (TGA); the composite had good thermal stability owing to the ceramic nature of Fe₃O₄. The Fe₃O₄@PANI/rGO has been applied as a potential sensing platform for electrochemical detection of hydrogen peroxide (H₂O₂). By the combined efforts of extended active surface area, active carbon support, more catalytic active sites and high electrical conductivity, the Fe₃O₄@PANI/rGO exhibited an improved performance toward the non-enzymatic detection of H₂O₂ in 0.5 M KOH with a fast response time (5 s), high sensitivity (223.7 μA mM⁻¹ cm⁻²), low limit of detection (4.45 μM) and wide linear range (100 μM–1.5 mM). Furthermore, the fabricated sensor exhibited excellent recovery rates (94.2–104.0 %) during real sample analysis.