Preparation And Electrochemical Detection Application Of 2D Molybdenum Disulfide-non-noble Nanocomposite

In recent years,MoS2 with excellent performance has been widely used in the field of electrochemical detection.However,bulk molybdenum disulfide has problems such as poor conductivity and low active sites,which affect its electrochemical detection performance.It can be improved by exfoliation to two-dimensional molybdenum disulfide and compounding with metal particles.In this paper,two-dimensional molybdenum disulfide was exfoliated and prepared by a low-cost and large-scale method and composited with high-conductivity metal particles,and applied to electrochemical detection of nitrite and uric acid.The main research contents of this paper are as follows:1.The preparation of 2D MoS2/Ni nanocomposite and electrochemical detection of nitrite.2D MoS2 was prepared by the combined method of high-efficiency,low-cost,and large-scale mechanical ball milling and liquid phase exfoliation,the lateral size of which was less than 200 nm.2D MoS2/Ni nanocomposite was prepared by chemical reduction method with nickel sulfate as the precursor in a two-dimensional molybdenum disulfide suspension.The effects of electrolyte pH,dispensing amount,concentration and compound ratio of 2D MoS2/Ni on the electrochemical detection of nitrite were studied.The detection mechanism is the electrocatalytic oxidation reaction of nitrite,two electrons are lost in the low scanning rate range,and one is lost in the high scanning rate range.The synergistic effect of two-dimensional molybdenum disulfide with irregular edges and abundant active sites and low-cost,high-conductivity nickel nanoparticles is conducive to electrochemical detection of nitrite,so that the detection results have a wide linear detection range(5-800 ?M),low detection limit(2.48 ?M)(S/N=3),good detection characteristics(stability,reproducibility and anti-interference).Corresponding tests have also been carried out on nitrite in tap water,which proves that it has a good recovery rate.In addition,2D MoS2/Ni can also be used for electrochemical detection of uric acid,which has a good detection effect(detection range:1-1000 ?M,detection limit:0.81 ?M).2.The preparation of 2D MoS2/Co nanocomposite and electrochemical detection of uric acid.2D MoS2/Co nanocomposite was prepared by chemical reduction method with nickel sulfate as the precursor in a two-dimensional molybdenum disulfide suspension.The effects of electrolyte pH,dispensing amount,concentration and compound ratio of 2D MoS2/Co on the electrochemical detection of uric acid were studied.The detection mechanism is that uric acid undergoes an electrocatalytic oxidation reaction and loses two electrons.The resulting sensor has a wide linear detection range(1-800 ?M),low detection limit(0.75 ?M)(S/N=3)and good detection characteristics.The uric acid in fetal bovine serum was also tested accordingly,which proved to have a good recovery rate.In addition,2D MoS2/Co can also be used for electrochemical detection of ascorbic acid,which has a good detection effect.