Preparation And Electrochemical Properties Of MoS₂ Nanosheets/carbon Nanofibers

Molybdenum disulfide?MoS₂?is a layered compound with graphene-like structure.It has unique structure,good physical and chemical properties,such as excellent charge-carrying mobility,high Young's modulus and chemical stability.There are many kinds of MoS₂ nanostructures,such as MoS₂ nanoparticles,MoS₂nanospheres,MoS₂ nanorods,MoS₂ nanotubes and MoS₂ nanosheets.Among them,the abundant bare edges of MoS₂ nanosheets make them show good biosensor performance in detecting biological molecules.The research shows that the three-dimensional?3D?hierarchical structure has better mechanical adhesion,excellent electronic transmission ability and more active edge position.The morphology and structure of MoS₂ nanosheets/carbon nanofibers composites were characterized by scanning electron microscopy?SEM?and X-ray diffraction?XRD?.From the SEM spectra,it can be seen that the electrospun carbon nanofibers are uniform in a diameter of about 200 nm,and the curved MoS₂nanosheets grow vertically on the carbon nanofibers with a diameter of about 400 nm.Comparing XRD with standard PDF card,we can confirm that the material is MoS₂nanosheet/carbon nanofiber composite.MoS₂ nanosheets/carbon nanofibers were assembled with ITO conductive glass to construct MoS₂ nanosheets/carbon nanofibers/ITO electrode for the detection of L-DOPA and UA in biosensors.The electrochemical performance of MoS₂nanosheet/carbon nanofibers/ITO electrode was tested by cyclic voltammetry?CV?and differential pulse cyclic voltammetry?DPV?.The experimental results show that the sensitivity of molybdenum disulfide nanosheets/carbon nanofibers/ITO electrodes for detection of L-DOPA and UA is 0.91 and 0.73?A·?M^-1,respectively,in the range of 0-60?M.The DPV determination of L-DOPA under the interference of UA and the DPV determination of UA under the interference of L-DOPA prove that the electrode has excellent selectivity,and the electrode exhibits excellent repeatability and stability.So MoS₂ nanosheets/carbon nanofibers/ITO electrode can be used in the electrochemical biosensor for the detection of L-DOPA and UA.