Preparation And Sensor Research Of Metal Oxides Nanofibers Based On Electrospining

Glucose quantitative determination is critically important to diabetic patients.Although enzymatic glucose sensor possess fast response,good selectivity and high sensitivity,its high cost,instability and poor reproducibility result in the complicated fabrication process and short life,And it is limited in the pratical using.Thus,people have focused on the nonenzymatic glucose sensors with low cost,good stability and reproducibility.The introduction of nano materials provide a boundless imagination for the development of sensors.Nano metal oxides can accelerate the electron transport rate because of its intresting nano morphology,biocompatibility,non toxicity and catalytic properties.As a simple and efficient method,electrospining is widely applied in preparation nano materials.Hence,this paper fabricated the metal oxides nanofibers with three dimensional structure by the electrospining technique and calcinations process,and applied it to the nonenzymatic glucose sensor.The main content are as follow:(1)Design a series of experiments by orthogonal design to investigation the influence of precursor solution concentration,electrospining speed,receiving distance and needle diameter.PVA is the precursor.Scanning electron microscope(SEM)was applied to characterize the morphology of nanofibers,nano measure was utilized to analysis the diameter and diameter distribution.The results indicate the precursor solution concentration have effect on the diameter.The analysis of experiment make us have a overview of electrospining,and provide a theoretical bassis to subsequent composite nanofibers preparation.(2)We fabricated a sensor material of NiO nanofibers with three dimensional nano structure by the electrospining technique followed by calcinations.Scanning electron microscope(SEM)was applied to characterize the morphology of nanofibers before and after calcination;The transmission electron microscope(TEM)were used to further characterize the morphology.X-ray diffraction(XRD)spectra was utilized to analyze the component of the sensor materials.The NiO nanofibers modified electrode presented a excellent performance in oxidation of glucose in an alkaline medium which had a linearcorrelation to glucose concentration in the range of 1?M to 745?M,a detection limit was calculated to be 0.33?M(S/N=3).(3)On the basis of chapter 3,an enhanced and sensitive nonenzymatic glucose sensor based on Li doped NiO nanofibers was successfully fabricated by electrospinning followed by calcinations.The morphology was presented by scanning electron microscopy(SEM)and transmission electron microscope(TEM).High resolution transmission electron microscope(HRTEM)and X-ray diffraction(XRD)spectra were employed to investigate the crystal structure.XPS was utilized to analyze the chemical state of element and further confirmed Li ions enter into NiO lattice.Then the electrochemical behavior exhibited fast electron transfer rate and enhanced elctrocatalytic ability to oxidation of glucose,which had a linear correlation to glucose concentration in the range of 0.5?M to 278?M,a detection limit was calculated to be0.1?M(S/N=3)and good selectivity to UA,AA DA.These indicate Li doped NiO nanofibers as the enhanced glucose sensing materials are potential candidate for nonenzymatic glucose sensor?...