Fabrication And Glucose Sensing Performance Of Co-based Nanosheets Materials

The impact of diabetes on social economy,medical treatment and human health is increasing all over the world.Therefore,the development of fast and accurate glucose detection technology is increasingly important,which is of great significance to the prevention and treatment of diabetes.With the continuous development of related research,electrode materials that can be applied to the fourth generation of non-enzymatic glucose sensors have become one of the research highlights.The non-enzymatic glucose sensors based on transition metal compounds can avoid the disadvantages of traditional enzyme-based glucose sensor,such as poor stability and poor reproducibility of detection results,and can also solve the limitation of large-scale production and application of noble metal electrode due to its high cost.Meanwhile,the principle of glucose catalytic oxidation and the characteristics of nanostructured materials indicate that the larger specific surface area of nanostructured electrode can provide more reactive sites and thus obtain excellent electrocatalytic performance.In this work,a new electrochemical deposition method based on the corrosion of amorphous alloy anodes(Zr₅₆Al₁₆Co₂₈ amorphous alloy)has been developed to obtain a self-supporting transition metal cobalt-based nanosheet structure(Co-NS@NF)for glucose sensing.Moreover,the performance of Co-NS@NF electrode was further improved by phosphorization and alkaline oxidation,the main contents are as follows:(1)The influence of deposition parameters on the morphology and composition of Co-NS@NF was studied systematically.It was found that a nano-porous structure composed of nanosheets with lengths of?297 nm could be obtained at 1.8 V vs.SCE for 3.5 h.The outer layer of nanosheets is Co(OH)₂and the inner part is Co.(2)The Co₃(PO₄)₂ nanosheets structure(CPO-NS@NF)was obtained by phosphating of Co-NS@NF with different conditions.The CPO-NS@NF-2 electrode phosphated at 573 K for 2 h exhibits excellent glucose sensing performance:the sensitivities for glucose detection are 2197?A·m M^-1 cm^-2 at 0-3 m M and 783?A·m M^-1 cm^-2 at 3-6 m M,the limit of detection is 563 n M.(3)The Co(OH)₂ nanosheets structure(Co(OH)2-NS@NF)was obtained via different alkaline oxidation of Co-NS@NF with the solution of(NH₄)₂S₂O₈and Na OH.The Co(OH)₂-NS@NF-60 electrode oxidized for 60 s shows ultrahigh sensitivities for glucose detection of3292?A·m M^-1 cm^-2 at 0-1 m M and 783?A·m M^-1 cm^-2 at 1-6 m M,and the limit of detection is as low as 60 n M.Furthermore,the CPO-NS@NF-2 and Co(OH)₂-NS@NF-60 electrodes exhibit excellent anti-interference,durability and actual detection performance for human serum,showing high application potential as non-enzymatic electrochemical glucose sensors.