Nickel oxide microfibers immobilized onto electrode by electrospinning and calcination for nonenzymatic glucose sensor and effect of calcination temperature on the performance

Nickel oxide microfibers (NiO-MFs) were directly immobilized onto the surface of fluorine tin oxide (FTO) electrode by electrospinning and calcination without using any immobilization matrix for nonenzymatic glucose sensor. Morphology and structure of NiO-MFs were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction pattern (XRD). The electrochemical and electrocatalytic performances of the NiO-MFs modified electrodes prepared at different calcination temperatures ranging from 300 to 500°C were evaluated by cyclic voltammetry (CV). The CV results have demonstrated that NiO-MFs modified electrode prepared at 300°C displayed distinct increase in electrocatalytic activity toward the oxidation of glucose, which is explored to develop an amperometric nonenzymatic glucose sensor. The NiO-MFs prepared at 300°C based amperometric nonenzymatic glucose sensor has ultrasensitive current (1785.41 μA mM(-1) cm(-2)) response and low detection limit of 3.3×10(-8) M (signal/noise ratio (S/N)=3), which are among the best values reported in literature. Additionally, excellent selectivity and stability have also been obtained.