Regulation Of The Structure And Component Of CuO/Cu₂O And The Application To Non-enzymatic Glucose Sensor

Glucose sensors have a wide range of applications in food,environmental monitoring,biomedicine industry and clinical diagnosis.Moreover,non-enzymatic glucose sensors developed based on transition metal oxides have attracted more and more attention in recent years due to their low cost,fast response speed and high sensitivity.As the typical transition metal oxide,copper oxide and cuprous oxide exhibit excellent structures and physical and chemical properties and have strong sensitivity to glucose,which can be used as excellent glucose detection materials.However,a single structure or composition is far from meeting the needs of daily life,so it is necessary to design the structure and composition to enhance its performance to the non-enzymatic glucose sensor.This paper creatively proposes a small-size hierarchical material preparation avenue,in which the structure and composition of CuO/Cu2O have been regulated to explore the"structure-activity relationship" with the performance.The structure and composition have been designed to achieve a leap in performance.The research and conclusion are as follows:(1)By utilizing the unique properties of the mixed valence state of transition metals and the ingenious design of nanostructure,a CuO/Cu2O hierarchical nanostructure has been constructed.The microwave process has been used to design the structure to achieve a superfine size preparation below 5 nm,thereby improving its sensitivity to glucose detection.The fast precipitation-assisted microwave method has been selected to prepared the barnyardgrass-like CuO/Cu2O heterostructured nanowires.In this microwave process,PEG200 plays an important role not only as solvent and reductant,but also as a template in the formation of the barnyardgrass-like structure.The composition and structure of the sample were measured by various characterization and testing methods.Due to the synergistic effect of hierarchical structure and mixed valence states assisting by small size effect,the barnyardgrass-like CuO/Cu2O nanowires exhibits excellent electrochemical performance to glucose detection.The testing results show that the sensitivity of 1281 mA mM-1 cm-2,the linear range of 0.05-2 mM,the detection limit of 16.7 mM,while the sample has good anti-interference and stability.(2)A fast and facile microwave process has been designed to prepare ternary CuO/Cu2O/SnO2 nanorods in one step,with porous Cu(OH)2 nanorods as reactant.The composition,morphology,structure and other characteristics of the sample were analyzed through XRD,XPS,TEM,SAED and other characterization methods,which contributes to the study of changes of each component in the growing process of CuO/Cu2O/SnO2 nanorods.The excellent biocompatibility and electron migration rate of SnO2 compensates for the slower electron transfer rate caused by the decrease in specific surface area and active sites of CuO/Cu2O/SnO2.Instead,it has obtained better glucose detection performance.This chapter also explored the catalytic oxidation of glucose.The testing results show that the electrode modified by this sample shows a higher sensitivity of 2043 mA mM-1 cm-2 and has good stability and selectivity.(3)In order to further improve the sensitivity of the materials for glucose sensing,this chapter took a comprehensive view of the common effect of the composition and structure on the material properties and then designed a method to prepare barnyardgrass-like CuO/Cu2O/SnO2 nano wires by using a fast microwave method with NaOH as protective agent and PEG200 as template.Owing to the synergistic effect of the multi-composition and hierarchical structure,the sample exhibits more excellent glucose detection performance.Through the analysis and test of the catalytic oxidation of glucose,it can be calculated that the sensitivity was 2112 mA mM-1 cm-2.Finally,by comparing the morphology,structure and properties of the CuO/Cu2O nanowires,CuO/Cu2O/SnO2 nanorods and CuO/Cu2O/SnO2 nanowires,we can get the influence of structure and composition on the glucose detection performance in the CuO/Cu2O system that the hierarchical structure can enhance the performance,while the third phase SnO2 can significantly improves the glucose catalytic performance more.That is,in this system,the composition has a greater impact on performance than structure.