Preparation And Properties Of Glucose Sensing Materials Based On Metallic Glass

Accurate and efficient detection of glucose is of great significance for many fields ranging from food test,fermentation,biochemistry,clinical diagnosis to environmental protection.Recently,electrochemical sensors based on transition metal like Ni and Cu and its metal oxides have demonstrated their potential as effective electrode candidates for electrochemical glucose sensors owing to their low cost and good biocompatibility.In this paper,Ni,Ti and Cu-based amorphous alloys were prepared as precursors by spin quenching,and nano-porous structures were prepared by using different dealloying methods.SEM,XRD and TEM were used to analyze the surface structure and chemical composition of the samples.The CV and CA were used to study the catalytic activity,stability and sensitivity of detecting glucose in alkaline solution.we further explored the active substances toward electrocatalytic glucose oxidation through in-situ electrochemical oxidation of dealloyed samples.Amorphous nanoporous nickel zirconium oxide(NP-Ni Zr O)was formed on the surface after dealloying Ni₆₄Zr₃₆ metallic glass,and the increase of dealloying time resulting in an increased i of the nanoporous.As active material for glucose sensor electrode,NP-Ni Zr O shows remarkable performance in detecting glucose,it has a short response time(3s)and a low detection limit(less than 2?M),and its sensitivity is 3.19 m A·cm^-2·m M^-1.In addition,continuous in-situ electrochemical oxidation was performed on the NP-Ni Zr O electrode,and the sensitivity of the electrode for glucose detection increased to 4.81 m A·cm^-2·m M^-1.According to XPS results,the Ni-Ni bonding energy peak disappeared after in-situ electrochemical oxidation,indicating electrode surface was further oxidized.The increased double-layer capacitor corresponds to improved electrochemically active area of the electrode after CV activation,revealing stronger catalytic activity.The surface of Ti₄₉Cu₃₀Zr₂₁ metallic glass is gradually crystallized with the formation of porous Cu and Cu₂O particles after dealloying in 0.01 M HF for 10 min,20 min,40 min,2 h,and 7 h.Both the contents of Cu as well as Cu₂O and the size of nanoporous on the ribbon's surface are increased with longer dealloying time,resulting in the formation of three-dimensional continuous nanoporous structure.The MG ribbons dealloyed for 20 min,40 min and 2 h were used as working electrodes.Their sensitivity of glucose detection in 0.1M Na OH solution is 2.79 m A·cm^-2·m M^-1,2.93 m A·cm^-2·m M^-1 and 2.71 m A·cm^-2·m M^-1,respectively.The detection range reached 4 m M.Different kinds of nano Cu O formed on the surface of the delloyed ribbon after in-situ electrochemical oxidation.The peak current of the CV curves and the sensitivities of detecting glucose decreased with the increasing of the number of cycles,which is due to the completely oxidation of low-valent Cu to Cu O on the surface.Therefore,the current density decreased because only Cu O works after in-situ electrochemical oxidation.A porous structure of Cu₆₅Ti₃₅ metallic glass is formed after dealloying in HF.However,the alloying of Ni in Cu₆₅Ti₃₅ metallic glass improved the corrosion resistance.The peak current density of the dealloyed ribbon to catalyze the oxidation of glucose is increased with the increased dealloying time,because the surface of the ribbon formed a porous ligament structure after the deepening of corrosion.More Cu-containing active substances are exposed on the surface of the ribbon,which generates more active sites and improves the catalytic performance of the electrode material.In addition,the addition of Ni can not only improve the stability of the electrode material after multiple voltampere cycles,but also enhance the stability of the electrode,which is due to the good redox reversibility of Ni.