Preparation Of Ionic Liquid Modified 2D Materials For Photoelectronics

Excellent properties in the fields of physics,chemistry and materials science making two-dimensional(2D)materials have attracted great interests in recent years.In order to develop the 2D materials,the research of new 2D materials has also attracted wide attention.The efficient preparation and photoelectric properties investigation of new two-dimensional materials have become a hot research direction in this field.In this thesis,we utilized ionic liquids to optimize the synthesis and modification of the new 2D materials including black phosphorus(BP)and antimonene(Sb).The high concentrate BP,polymer ionic liquid passivated BP and polymer ionic liquid modified Sb were prepared.We further investigated the photoelectronic properties of these organic-inorganic composites with nonlinear optics and photoelectric conversion.This dissertation mainly includes the following five parts:1.High-concentration BP nanosheet dispersion was obtained by ultrasonic assisted with ionic liquid.The composite was applied to nonlinear optical devices.The black phosphorus was efficiently exfoliated by ionic liquid for the strong interaction between ionic liquid and black phosphorus.The saturation absorption nonlinear optical properties of the black phosphorus were investigated by Z-scan technique.The material was further applied to mode locking applications and achieved mode locking in the 2 μm wavelength region.2.Environmentally stable BP nanosheet were prepared and the properties of the material in flexible photodetectors were investigated.The high-concentration and passivated BP was obtained by the assistance of diluted polymer ionic liquid.The stability of polymer ionic liquid/BP nanocomposites were tested in solution,laser and ordinary air environment by UV,Raman,SEM and TEM.Due to the high mechanical strength and good electrical conductivity properties of the polymer ionic liquid,the flexible photodetector based on the composite nanomaterial exhibits excellent properties.3.The two-dimensional Sb modified by polymer ionic liquid was prepared and its photoelectric response properties were studied.A high concentration of Sb dispersion was obtained by liquid ultrasonic exfoliation with the assistance of polymer ionic liquids.The structure and optical properties of the material were studied by UV,Raman,AFM and TEM.A uniform Sb film was obtained on the surface of the conductive glass by electrochemical deposition,and the photoelectric response properties of the material were further explored.4.BP and antimony oxide nanosheets were prepared by electrochemical exfoliation method.The photoelectric response properties were studied.The effect of different electrolyte types,concentrations and different voltages on the nanomaterials was investigated.The structure,elemental composition and optical properties of these materials were investigated by means of UV,XRD,Raman and TEM.The photoelectric response of these materials was investigated.5.A series of non-layered transition metal carbide 2D materials were prepared and the nonlinear optical properties of the materials were studied.Utilizing the hardness anisotropy of this series of non-layered materials,we obtained the corresponding 2D materials by solvent-assisted slip cleavage method.The structure,morphology and optical properties of the materials were studied by UV,XRD,Raman,XPS,TEM,AFM and Z-scan.The nonlinear saturated absorption properties of the 2D TiC nanosheets in this series of materials are most prominent.TiC nanosheets was further applied to laser mode-locking and achieved the 1 μm and 2 μm wavelength regions mode locked.