Research On The Design?Fabrication And Strain Sensing Properties Of Graphene-MoS₂ Composite Structure

Two-dimensional atomic crystal materials have received significant attention owing to their unique fundamental physical and chemical properties.Among various two-dimensional?2D?materials,graphene and molybdenum sulfide?MoS₂?have attracted enormous research interest.Graphene and2D MoS₂ can produce a large resistance change steadily under the micro-deformation.They can bear a greater elastic strain than the corresponding bulk material without causing breaking of the structures,which make them have excellent strain sensing properties.The characteristic makes them have an important potential application in health monitoring,wearable devices and electronic skin.In this thesis,we report an easy and fast chemical vapor deposition?CVD?method for the growth of MoS₂and graphene woven fabrics?GWFs?.We construct strain sensors and test strain sensing properties of the devices based on different substrates.Consequently,strain sensing mechanism and application fields are discussed.Besides,we have designed a composite structure composed of graphene and MoS₂,mechanical-light-electric field coupling characteristics of the materials have been studied.The main work and results are concluded as follows:We fabricate the meshy MoS₂ film on molybdenum?Mo?mesh based on the CVD growth for the first time.The measured result shows that a continuous uniform film is prepared.Afterwards,we transfer the MoS₂ films onto PDMS and construct the corresponding strain sensor,which the sensing properties are tested.And strain sensing mechanism is in detailed revealed.Furthermore,we fabricate graphene woven fabrics on Cu mesh through the CVD method under a condition of low pressure and high temperature.The GWF film are transferred onto other insulated substrates such as silicon?PDMS and double sided tape using substrate etching methods,which are constructed as strain sensors and measure the strain sensing properties respectively.The result verify the application prospect of GWF strain on the field of electronic skin and explain the strain sensing mechanism of graphene from the micro and macro aspects.We also construct a Graphene-MoS₂ composite structure srain sensor.We fabricate graphene on Cu foils through the CVD method and transfer graphene films onto SiO₂/Si substrates using using PMMA coating and substrate etching methods.The result showed that the large area continuous uniform film was formed on the surface of the Cu foil.Then we transfer graphene film onto PET substrate and fabricate a graphene/PET sensor.We find that a resistance and a voltage response will be produced under the condition of pressure and vibration.Besides,we design and construct a sensor based on the composite structure composed of graphene and MoS₂,which have strain sensing characteristics and photoelectric response properties.We demonstrate that Graphene-MoS₂ composite structure play an important role in constructing force-light-electric field coupling strain sensor.