Non-enzymatic approach of H₂O₂ and glucose sensing using NiO–MoS₂-derived electrochemical sensor

At present, selective and accurate determination of hydrogen peroxide (H₂O₂) and glucose has become essential for routine diagnosis. The present work demonstrates the hydrothermal synthesis of NiO nanosheet (NS)–MoS₂-based composite system for non-enzymatic electrochemical detection of H₂O₂ and glucose. To understand the structure, morphology and elemental constituents of the prepared composite system, various characterization techniques were employed, namely XRD, FTIR, FESEM, TEM and EDX. Redox activity and charge transfer process of the NiO–MoS₂-based sensor electrode towards H₂O₂ and glucose were realized via using electrochemical techniques: cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry. To be mentioned, limit of detection (LOD) and sensitivity for detection of H₂O₂ are calculated to be 3 µM and 3925 µA mM⁻¹ cm⁻², respectively, under the linear range of 5–455 µM in 0.1 M PBS solution. Similarly, the LOD and sensitivity for sensing glucose is estimated to be 3.53 µM and 1880 µA mM⁻¹ cm⁻², respectively, under the linear range of 5–370 µM in 0.1 M NaOH solution. The cost-effective fabricated sensor exhibited good stability with a high selectivity towards the specific analytes only.