Metal Oxide Design Of Cobalt And Copper With Hierarchical Porous Structure And Its Application In Non-enzymatic Glucose Sensor

Glucose sensors can detect glucose in human blood and have profound implications for the diagnosis of diabetes.Currently,glucose sensors used in daily life are mostly based on glucose oxidase.However,the inherent disadvantages of enzymes,such as high cost,poor stability,and strict test conditions,make it difficult to meet the growing social needs.Non-enzymatic glucose sensors developed with metal oxides have received much attention because of their low cost,high stability and fast response.Consider the specific composition and structure is a key step to improve the glucose sensor.Through the design and control of the experiment,this paper explored the glucose detection sensitivity of metal oxides which based on the precursors of Cu and Co elements.(1)CuO and Co3O4 with nanostructured were prepared by a simple solvothermal method.Their structures were characterized and their electrochemical performances toward detectionwere tested.The results showed that the CuO detection limit was 24?M,the linear range was 24 ?M-0.4 mM,the sensitivity was 747 ?A ·mM-1·cm-2,the Co3O4 detection limit was 16 ?M,the linear range was 16 ?M-0.4 mM,and the sensitivity was 1414 ?A·mM-1·cm-2 with good noise immunity.(2)Hollow spherical CuCo2O4 was prepared by solvothermal method.The structural characterization showed that the synthesized product was a size of 500 nm polycrystalline CuCo2O4.The glucose-sensitivity test of the materials modified electrode showed excellent performance with a detection limit of 2.6 nM,a linear detection range of 2.6 nM-0.75 mM,and a sensitivity of 1854.57 ?A ·mM-1·cm-2.This test result has been greatly improved compared to the corresponding single metal oxides,which is due to the fact that the copper cobalt oxide spinel has a higher electrical conductivity and higher electrochemical activity than the single metal oxides.(3)In order to further improve the glucose-sensitive properties of the material,we use a three-dimensional network structure of Cu foam as the conductive substrate,through solvothermal reaction and subsequent annealing,to obtain CuCo2O4 nanosheet arrays which grown on copper foam substrate.These nanosheets are porous with a thickness of 50 nm.Electrochemical detection of glucose exhibited a high sensitivity of 20981 ?A·mM-1·cm-2,a detection limit of 1 ?M.The detection range is 1 ?M-1 mM.The result of this test has been greatly improved compared to powder CuCo2O4.This can be attributed to the in-situ growth of CuCo2O4 during the electrode design.process.The electrode constructed by.this method can greatly improve the ability of electron transfer and collection.