Preparation And Glucose Sensing Properties Of Ni-based/Polyurethane Composite Electrode

Glucose sensors have important applications in many fields such as medical treatment,food processing,and environmental analysis.Among them,flexible non-enzymatic glucose sensors have become a research trend.At present,most of the electrode materials of non-enzymatic glucose sensors have obvious drawbacks and the preparation process is complicated,which hinders their future applications.Therefore,it is of great significance to develop a highly sensitive and flexible electrode material.Polyurethane sponge has attracted attention in the sensor field because of its light weight,flexibility and low cost.At the same time,nickel-based catalysts have good electrocatalytic properties for glucose and are widely used in non-enzymatic glucose sensors.In this paper,polyurethane sponge was used as the electrode substrate to prepare the nickel-based/polyurethane composite electrode materials and study their performance for non-enzymatic glucose detection.In this paper,nickel hydroxide/polyurethane electrode(Ni(OH)₂/PU)was prepared by directly loading nickel hydroxide on a flexible porous polyurethane sponge(PU)substrate by one-step hydrothermal method.Graphene oxide(GO)was prepared by the Hummers method and reduced graphene oxide(RGO)was prepared by the microwave thermal reduction method which was used as a support material.The RGO/PU electrode was prepared by the impregnation and drying process.A nickel/reduced graphene oxide/polyurethane electrode(Ni/RGO/PU)was prepared by constant potential electrodeposition.The composition,microscopic morphology and electrochemical performance of the composite electrode were analyzed through XRD,XPS,Raman,SEM,TEM,CV,CA,and EIS tests.The performance of Ni(OH)₂/PU electrode and Ni/RGO/PU electrode for glucose detection were also investigated.The Ni(OH)₂/PU electrode had a high sensitivity of 2845?AmM^-1cm^-2 and a low detection limit of 0.32?M(S/N=3)in the detection range of 0.01 mM-2.06 mM.In addition,Ni(OH)₂/PU electrode also had excellent selectivity,repeatability and stability,and effectively detected glucose in fetal bovine serum(FBS).The three-dimensional porous structure of the polyurethane sponge provided a large surface area and the Ni(OH)₂ uniformly loaded on the electrode surface provided a wealth of electrochemically active sites,which facilitated the reaction of glucose on the electrode surface and achieved a high level of glucose detection performance.The influence of electrodeposition time on the performance of Ni/RGO/PU electrode was investigated through EIS and CV tests.The results showed that the electrode had the smallest impedance and the largest electrochemical active area when the electrodeposition time was20min.Ni/RGO/PU electrode had a high sensitivity of 20050?AmM^-1cm^-2 and a low detection limit of 0.045?M(S/N=3)in the low concentration range of 0.01 mM?2.0 mM and had the sensitivity of 4876?AmM^-1cm^-2 and a detection limit of 0.186?M(S/N=3)in the high concentration of 2.0 mM?4.0 mM.The Ni/RGO/PU electrode also had excellent selectivity,repeatability and stability,and effectively detected fetal bovine serum(FBS)in glucose.Compared with the Ni(OH)₂/PU electrode,the sensitivity of the Ni/RGO/PU electrode was significantly improved.RGO improved the conductivity of the electrode and provided a fast electron transmission channel,and the synergistic effect of RGO and Ni realized the excellent detection performance of the electrode for glucose.