Research On Graphene Based Self-powered Biosensors

With the development of technology,the world has entered an era of interconnected things.Sensors,as the foundation of the Internet of Things,play a role in perception and recognition,providing a basis for application layer data analysis.As a type of sensor,glucose biosensors have wide applications in medical,environmental,food monitoring,and other fields.At present,the application of portable and implanted glucose sensors is constantly increasing,and the output signal of the glucose sensor can also be transmitted to devices such as mobile phones and bracelets for signal transmission,achieving real-time detection.Glucose self powered biosensors do not require additional power supply equipment and are a hot research topic in related fields.Self powered biosensors based on Graphene are expected to have both excellent sensing performance and power supply performance,and have important application prospects.This paper focuses on glucose self powered biosensor based on Graphene,and the main work is as follows:The power supply performance of Graphene and its composites as biosensor cathode was studied.Graphene itself has the advantages of large specific surface area,high energy density and power density.Further combining it with transition metals can not only solve the problems of agglomeration and stacking of Graphene,but also improve the defects of poor conductivity of transition metals.Therefore,Graphene composites are expected to have better power supply performance.The experimental results show that the specific capacitance of Graphene is twice that of graphite foil,and the specific capacitance of Graphene composites is 27 times that of Graphene,reaching 556.563 mF·cm-2;The power supply performance of Graphene cathode is 2.4 times that of graphite foil,and the power supply performance of Graphene composite cathode is 3 times that of Graphene.The peak power density corresponding to 10VM glucose is 6.216μW·cm-2.The sensing properties of Graphene and its composites as biosensor anode were studied.The functional groups and structural defects on the surface of Graphene are conducive to the immobilization of active substances,and the combination with transition metals can increase the active area of Graphene composites,thereby amplifying the sensing signal and improving the catalytic oxidation performance of the electrode for glucose.The experimental results show that the interface of the composite can be adjusted by changing the composite mode of copper and nickel on the surface of Graphene,and the maximum sensitivity can reach 15.634μA·mM-1·cm-2,which is about 150 times that of the single Graphene anode;By changing the thickness of different composition layers of Graphene composites,the amount of active substances in the composites can be adjusted,and the sensitivity is improved to 18.099μA·mM-1·cm-2.The sensing and power supply properties of Graphene and its composites as both anode and cathode of biosensors were studied.The combination of Graphene and transition metals will increase the active area of the anode and enhance the catalytic oxidation capacity of glucose;The combination of Graphene and transition metals can improve the conductivity of the cathode,increase the power density and energy density,and improve its electrical storage performance.The experimental results show that the sensing performance and power supply performance are significantly improved by using Graphene and transition metal composites as both anode and cathode,and the sensitivity of the sensor reaches 24.436μA·mM-1·cm-2;The maximum power density peak corresponding to 10mM glucose is 134.901μW·cm-2.