Facile synthesis of NiCo₂O₄@Polyaniline core-shell nanocomposite for sensitive determination of glucose

In this work, the core-shell structure of NiCo₂O₄@Polyaniline (NiCo₂O₄@PANI) nanocomposite is fabricated via a facile hydrothermal treatment followed by a post-Polyaniline (PANI) coating process. The synthesized materials are characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectrometer. The biosensing properties of NiCo₂O₄@PANI composite and NiCo₂O₄ nanoparticles toward glucose are studied based on glassy carbon electrode. Electrochemical studies indicate that the obtained core-shell NiCo₂O₄@PANI composite shows higher electrocatalytic activity toward the oxidation of glucose, compared with NiCo₂O₄ nanoparticles. The enhanced performance is related to the core-shell structure of NiCo₂O₄@PANI composite and the outstanding conductivity of the polyaniline shell. At a potential of +0.5V, the NiCo₂O₄@PANI nanocomposite modified glass carbon electrode demonstrates a wide linear range up to 4.7350mM with sensitivity of 4.55mAmM^-1cm^-2 and detection limit of 0.3833μM. It also shows significant electrochemical stability, good reproducibility and excellent selectivity. The results suggest that the NiCo₂O₄@PANI nanocomposite is a promising electrode material for electrochemical biosensor.