| In the past 5 years,Graphene show the unique physical and chemical properties has led to the rise of 2D thin material, 2D thin material with confined effect and quantum size can show some properties which other 3D(particles and micro-nano) materials do not have, such asspecial photoelectric and catalytic performance, single layer or layers of carbon material synthesis method has been overcome by researchers and the synthesis of single or several layers atomic group 2 D metal material is still facing great difficulties and challenges.Semi-metal bismuth is a unique kind of material, has a wide indirect band gap, high anisotropy of Fermi surface band, low carrier density, small effective mass and the little mass free path, 2 D or 1 D morphology of bismuth asa ideal simple structure toolsfor researchingof physical phenomena, can be used to open a new gate to study the band theory of semiconductor physics. At the same time, its bismuth telluridenanomaterials,for its new application in microscopic physics and structural components such as photoelectric diode array and unique applications in superconductors and thermoelectric performance, makes the synthesis of 2Dbismuth telluride nanomaterials received extensive attention of many research groups in a widely range.This article mainly discussed the bismuth elemental and bismuth telluride2 Dultrathin material synthesis, the third chapter basically focus on the nanoscale Bi crystallite morphology and size control,provide a new method of low temperature liquid phase synthesis of different boundary shape of ultra-thin new method for 2D Bi nanosheets.System research of the liquid phase chemical reduction method with polymer additives controlling preparationof Bi two-dimensional nanomaterials, morphology, and increase the purity during preparation process.Obtained monodisperse, thickness of Bi nanosheets were characterization by TEM and AFM were only 1.3 nm, grain of Bismuth is single crystal with(001) crystal plane arrangement(the thickest of no more than 2.5 nm the boundary of the two different morphology(hexor rectangular pieces) of ultra-thin bismuth.TEM and XRD analysis results of the two kinds of ultra-thin nucleation growth mechanism of the nanometer material has made the formation detailed.In the fourth chapter on the physical properties of ultrathin bismuth nano semiconductor make detailed analysis, infrared spectroscopy and electrochemical catalytic experiments to study the L- P subband migration phenomenon, first observed infrared absorption peak at 1620 cm- 1, and set up the physics model of the indirect band gap width of its semiconductor effective quality and make estimates, get the largest band gap is 203 mev, draw the energy band structure of two-dimensional ultra-thin bismuth materials. Methanol as electro-catal ysis experimental characterization of its macro ultra-thin properties and resistance to carbon monoxide poisoning, performance contrasted with the business performance of electrode.In the fifth chapter Tellurium acid sodium as the source of tellurium, using the method of adjusting the wet chemical synthesis in the third chapter, the synthesis of polymer modified regulation ultra-thin 2 D bismuth telluride material, studies its thermoelectric properties change, and the influence of nanometer chip morphology changes affect the thermoelectric performance of concrete. |
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