Fabrication And Catalytic Property Towards Glucose Oxidation Of Nanostructured Materials From TiCu Amorphous Alloy

Diabetes is a kind of metabolic disease in which the body is unable to produce enough insulin,resulting in elevated glucose levels in the blood.A report released by WHO shows that the incidence rate of diabetes has been increasing rapidly in recent years.It is become a serious global health care problem which human being have to face to.In the prevention and treatment of diabetes,accurate detection of blood glucose concentration plays an important role.Therefore,rapid,economic and reliable detection of blood glucose concentration has become the focus of research in this field.Up to now,glucose sensors have experienced four generations of development.The fourth generation enzyme-free glucose sensor is a device based on the corresponding current response of glucose molecules after catalytic oxidation on the electrode surface.Enzyme free glucose sensors exhibit the advantages of wide range of materials,high stability and simple preparation.Recently,with the development of nanotechnology,enzyme-free glucose sensor with nanostructure has become one of the important topics due to its large catalytic active sites.The combination of catalytic active elements and nanostructure is beneficial to the improvent of catalytic activity.In this paper,the effects of different Nicontent,modification by adding Niand Co transition metals,on the morphology of the nanotubes and their catalytic properties for glucose were studied.The corresponding catalytic mechanism were discussed.The main results of this researchare listed as following:(1)The Ti₆₀Cu_40-xNi_x(x=0,1,5,10 at.%)amorphous ribbons as precursors were obtained by single copper roller quenching method.Nanotubes were prepared by potentiostatic anodization of the TiCubased amorphous.The effects of Nicontent and anodizing voltage on the microstructure of the amorphous alloy precursor were systematically studied.The experimental results show that the morphology of nanotubes can be effectively controlled by changing the Nicontent and anodizing voltage.With the increase of Nicontent,the diameter of nanotubes increases from 18.4 nm to 26.8 nm.When the nanotube structure is applied to glucose catalytic test,it is found that with the increase of Nicontent,the glucose sensing sensitivity of the electrode increases from 415.3?AmM^-1cm^-2to 531.9?AmM^-1cm^-2(detection range:0-3.2 mM).This is because the electrochemical active area of the electrode material increases from 2.28 cm^-2to 15.50 cm^-2,and Nielement has good electrocatalytic activity,so the addition of Nielement improves the glucose sensing performance of the material;(2)Decoration of Niand Co elements on the surface of the TiCuO nanotube array by electrochemical pulse deposition method was carried out on TiCuO nanotube with the formations of Ni-Co nanonet modified TiCuO nanotubes((Ni-Co)/TiCuO NTs).The effects of deposition current density on the morphology of nanocomposites were studied.In addition,the composited electrode was applied to the detection of glucose sensor.The results show that,(Ni-Co)/TiCuO NTs has glucose sensing sensitivity as high as 3340?AmM^-1cm^-2(detection range:0-1.1 mM)compared with TiCuO nanotubes,and can be used for the detection of glucose concentration in real human serum.The nanocomposite structure obtained in this paper can effectively improve the catalytic performance of glucose,because the nanocomposite structure which formed by double transition metal decorated nanotubes has larger electrochemical active area,smaller charge transfer resistance and faster electron transfer rate.The electrochemical active area of(Ni-Co)/TiCuO NTs electrode material(57.25cm-²)is 25 times that of ticuo NTS electrode material(2.28 cm^-2).At the same time,the existence of transition metal elements Niand Co greatly improves the electron transfer ability of the materials.Compared with the charge transfer resistance R_ct(1046 Ohm·cm²)and the apparent heterogeneous electron transfer rate K(1.93 s^-1)of TiCuO nanotubes,the modified nanocomposite electrode materials have lower charge transfer resistance RCT(364 Ohm·cm²)and higher apparent heterogeneous electron transfer rate K(5.22 s^-1)?...