Research On Non-enzymatic Glucose Sensor Based On Silver/nickel Coated Yarn

Smart wearable devices have a wide range of applications in the field of human health monitoring,which promotes the rapid development of flexible sensors.Glucose sensor is an important part of wearable electronic devices,which can convert glucose concentration in blood into electrical signal output,thereby effectively monitoring human blood sugar.Currently,most of the sensors available on the market for glucose detection are of low accuracy and are mostly electronic devices not suitable for human wearable applications.Therefore,the development of a glucose sensor with excellent sensing performance and flexibility is still a key technology for human health monitoring.In this paper,the nickel-based flexible electrode was prepared by constant potential deposition using silver-coated yarn(SCNF)as a flexible substrate,and its non-enzymatic glucose sensing properties were investigated.The specific research content is as following:(1)The SCNF@Ni yarn electrode was prepared by depositing metallic nickel(Ni)on the surface of SCNF by direct electrochemical deposition.The morphology and structure of the electrode surface were characterized,and its glucose sensing performance was investigated.The results show that the SCNF@Ni yarn electrode with an electrodeposition time of 300s and applied potential of 0.5 V has the best sensing performance in the linear ranges of 2?M?1m M and 1m M?22m M,with sensitivities of 115.26 and 67.37?A m M^-1cm^-2,respectively,and response times less than 7s.In addition,it also has good anti-interference performance,repeatability and reproducibility,and the synergistic effect of Ni and Ag improves the charge transfer efficiency and strengthens the glucose sensing performance.(2)On the basis of the SCNF@Ni yarn electrode,the SCNF@Ni@Ni Co-LDH yarn electrode was prepared by further depositing cobalt nickel hydroxide(Ni Co-LDH)on its surface by secondary deposition to improve its sensing performance.The results demonstrate that the electrode with an electrodeposition time of 400s and applied potential of 0.5V has the best sensing performance in the linear ranges of 2?M?1m M,1m M?10m M and 10m M?26m M,with sensitivities of 191.44,88.18 and 51.85?A m M^-1cm^-2,and the response time less than 4s.It has better repeatability,reproducibility and stability.Because Ni Co-LDH exists on the surface of the electrode in the form of petal-like nanosheets,the specific surface area is increased,more active sites are provided,and the electron transfer efficiency is accelerated,thereby further enhancing the glucose sensing performance.(3)The flexibility test of SCNF@Ni and SCNF@Ni@Ni Co-LDH yarn electrodes by bending motion.The results show that both electrodes can maintain good conductivity and sensing performance after 1000 bending cycles,indicating that the two electrodes have good flexibility.In addition,it was found that changing the p H value,temperature and Cl^-concentration of the electrolyte has a significant effect on the sensor performance of the yarn electrode,and the SCNF@Ni@Ni Co-LDH electrode has better performance than the SCNF@Ni electrode Cl^-resistance.