Synthesis and characterization of Ag doped CuO nanorods electrode for non-enzymatic glucose sensing

The development of stable and highly sensitive non-enzymatic electrochemical glucose sensors is essential primarily to treat diabetes. In this work, Ag-doped CuO nanorods electrode were prepared using hydrothermal technique and used for non-enzymatic glucose detection. The structural, morphological, and chemical composition characteristics of the pristine and Ag-doped electrode were analysed using X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy(HRTEM) with high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) elemental mapping and X-ray photoelectron spectroscopy (XPS), confirming successful formation of nanorods and incorporation of Ag in CuO. Electrochemical glucose sensing performance of doped and undoped CuO nanorods was characterized using cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). In comparison to the pristine CuO nanorods, the electrocatalytic activity toward glucose oxidation is found to be enhanced after incorporation of Ag into the CuO lattice effectively. Ag-doped CuO exhibits a sensitivity of 2520 µAcm^-2 mM^-1 in the linear range of 5 µM to 900 µM with a detection limit of 2.5 µM. The sensor also shows good reproducibility, stability, and selectivity against common interfering species.