Synthesis And Application Of Molybdenum Disulfide-based Nanocomposites

Recently,controallable synthesis and application of graphene and graphene-like two-dimensional layered nanomaterials have attracted the attention of scientists.To obtain better chemical/physical properties of the material,more and more researchers pay attention to developing two-dimensional nanocomposites.Up to now,two-dimensional nanocomposites had an extensive application in new energy,electrocatalysis,biosensing,medical analysis and other fields due to their synergistic effect.This paper focused on the controllable synthesis and electrochemical application of molybdenum disulfide-based nanocomposites.The main research contents were listed as the following:（1）We used a microwave-assisted hydrothermal method to synthesize platinum nanoparticles-decorated molybdenum disulfide（MoS₂-Pt NPs）nanocomposites.A MoS₂-based electrochemical sensor has been constructed to simultaneously detect dopamine（DA）and uric acid（UA）.Under the optimal condition,the peak currents of the electrochemical sensor were linear with the concentrations of DA and UA in the range of 0.5-150μM and 5-1000μM with detection limit of0.17μM and 0.98μM,respectively.The sensor also had good stability and reproducibility,suggesting the MoS₂-based sensor should be employed to examine DA and UA in real samples.（2）We used a simple and efficient one-step synthesis method to prepare shape-controlled’palladium-platinumbimetallicfunctionalizedmolybdenumdisulfide(MoS₂-Pd_x Pt_y)nanocomposites.Individually changing the molar ratio of potassium hypochlorite and potassium hypochlorite from 10:1,1:1 to 1:5,the shapes of the MoS₂-Pd_x Pt_y turned from spherical,concave cubes to flower-like.Taking flower-like MoS₂-Pd₁Pt₅ nanocomposites as an example,the influences of experimental conditions on the nanocomposites’morphology,size and density were studied.On the basis of successful synthesis,the electrocatalytic activity toward methanol of MoS₂-Pd_x Pt_y nanocomposites was investigated.The experimental results showed that the three MoS₂-Pd_x Pt_y nanocomposites have excellent electrocatalytic activity toward methanol.Moreover,the catalytic peak currents of MoS₂-Pd₁Pt₅ nanocomposite were almost 4.5 and 1.8 times larger than that of MoS₂-Pd₁₀Pt₁ and MoS₂-Pd₁Pt₁,respectively.（3）We used a simple wet chemical synthesis method to prepare Prussian blue（PB）cube-decorated molybdenum disulfide（MoS₂-PBNCs）nanocomposites.PB is often used as an efficient mediator and nanoenzyme to develop electrochemical sensors.Therefore,the as-prepared MoS₂-PBNCs nanocomposites could be employed to construct electrochemical sensors for both nonenzymatic detection of H₂O₂ and label-free detection of carcinoem-bryonic antigen（CEA）.The experimental results showed that the reduction peak currents of MoS₂-PBNCs nanocomposites were linear with the concentration of H₂O₂ in the range of 0.01-300μM H₂O₂ with the detection limit of4.1 n M.For CEA detection,the oxidation peak currents of MoS₂-PBNCs nanocomposites had a good linear relationship with the logarithm of CEA concentration in the range of 0.005-10 ng/m L with the detection limit of 0.54 pg/m L.At the same time,the immunosensor based on MoS₂-PBNCs nanocomposites also had good stability,selectivity and reproducibility,which could be used for CEA detection for human serum samples.