Facile hydrothermal synthesis of NiO/rGO nanocomposite electrodes for supercapacitor and nonenzymatic glucose biosensing application

The NiO/rGO composites are synthesized via a hydrothermal method followed by annealing treatment with varying graphene oxide concentrations. The structural and morphological characterizations of synthesized samples are done by XRD, FT-IR, Raman, and FE-SEM. The electrochemical supercapacitor performance of prepared electrodes is characterized by CV, GCD, and EIS studies. The NiO/rGO composite achieved the highest specific capacitance of 727.1 F g−1 at 1 mA cm−2 current density and showed good cyclic stability of about 80.4% over 9000 cycles. In a nonenzymatic glucose sensing study, the sensing properties are analyzed by CV and chronoamperometry. The NiO/rGO composite showed the highest glucose sensitivity of 442.4 μA mM−1 cm−2 with correlation coefficient R2 = 0.9964 and LOD of 7.42 μM.