硼基低维材料的制备和光电性能研究

发布时间：2018-05-06 03:39

本文选题：超薄硼纳米带 + 六硼化铈　；参考：《信阳师范学院》2015年硕士论文

【摘要】：硼基材料具有熔点高、硬度大、耐磨损、耐腐蚀,光电性能好的特点,常用于国防、航空、民用等领域。理论和实验研究表明,硼基纳米材料具有非常丰富的形貌特征和优良的物理化学性质,这些特性决定了它们会有非常广阔的应用前景。因此,硼基纳米材料的研究有着非常重要的科学意义和广泛的应用价值。本论文分为以下三个部分：一、使用乙硼烷作为硼源,通过热分解的方法制备出超薄单晶硼纳米带。与以往较厚的硼纳米片相比,文中的纳米带表现出了明显的性能优势：①电子发射特性好。常温下开启电场(3.6V/gm)和阈值电场(5.08Vμm-1)低,且场发射性能稳定；变温的场致发射表明,随着温度的升高,开启电场和阂值电场不断下降,而场发射电流密度则不断升高,其内在机制可能是：高温下材料表面气体吸附/脱附效应导致了有效功函数的降低。②电子迁移率高。实验表明,超薄单晶硼纳米带的电子迁移率高达1.26×10-1cm7V-1s-1,比文献报道的高两个数量级。③导电性高。常温下单晶硼纳米带的电导率为2.8×102Ω2-1cm-1,这是迄今为止性能最好的；电子输运特性表明：高温下电子跃迁符合双激活电导机制,低温下电子行为符合Mott变程跃迁模型。④光探测性能好。测试结果表明：单晶超薄硼纳米带灵敏度高,响应速度快,量子产率高,稳定性好,明显优于其他报道中的硼纳米材料。二、以CeCl3作为铈源,乙硼烷作为硼源,碳布作为沉积衬底,在高温低压下制备了大面积CeB6纳米线阵列。与以往报道不同的是,本论文中的纳米线是以柔性极好的碳布作为沉积衬底,这些成果将有望在未来的柔性电子显示器件中得到广泛应用。利用X-ray粉末衍射仪(XRD)、拉曼光谱(Raman)、场发射扫描电镜(FESEM)、透射电镜(TEM)、高分辨透射电镜(HRTEM)、选区电子衍射(SAED)、X-ray光电子能谱(XPS)等多种测试手段对样品进行分析,结果显示：衬底上有大面积的纳米线沉积,长度约为lOμm,直径约为100nm,沿着[100]方向生长。电子发射结果正在进一步测试之中。三、以乙硼烷作为硼源,甲烷作为碳源,成功合成了大量的碳化硼(BxCy)纳米带和纳米线阵列,经由X-ray粉末衍射仪(XRD)、拉曼光谱(Raman)、场发射扫描电镜(FESEM)和能谱(EDS)初步表明,所合成的样品为碳化硼低维材料。场发射测试结果初步表明,碳化硼的电子发射特性优异；单根纳米材料的电子输运表明,其导电性能良好。碳化硼材料的光电探测特性及进一步的物理化学表征正在进行中,期望有较好的性能。
[Abstract]:Boron-based materials with high melting point, high hardness, wear resistance, corrosion resistance, good photoelectric properties, often used in national defense, aviation, civil and other fields. Theoretical and experimental studies show that boron based nanomaterials have very rich morphologies and excellent physical and chemical properties, which make them have a very broad application prospect. Therefore, the research of boron-based nanomaterials has very important scientific significance and wide application value. This thesis is divided into the following three parts: Firstly, ultrathin single crystal boron nanobelts were prepared by thermal decomposition using ethylborane as boron source. Compared with the thicker boron nanocrystals in this paper, the nanobelts in this paper show obvious performance advantage: 1 electron emission characteristics. At room temperature, the open electric field (3.6V / gm) and the threshold electric field (5.08V 渭 m ~ (-1) are low, and the field emission performance is stable. The field emission at variable temperature shows that the open electric field and the threshold electric field decrease with the increase of temperature, while the field emission current density increases. The intrinsic mechanism may be that the gas adsorption / desorption effect on the surface of the material at high temperature results in the decrease of the effective work function and the high mobility of 2.2electron. The results show that the electron mobility of ultra-thin single crystal boron nanoribbons is as high as 1.26 脳 10 ~ (-1) cm7V-1s-1, which is two orders of magnitude higher than that reported in literature. The conductivity of single crystal boron nanobelts at room temperature is 2.8 脳 102 惟 2-1cm-1, which is the best so far. At low temperature, the electron behavior accords with the Mott variable range transition model. 4. The optical detection performance is good. The results show that the single crystal ultra-thin boron nanobelts have high sensitivity, fast response speed, high quantum yield and good stability, which are obviously superior to other reported boron nanocrystals. Secondly, large area CeB6 nanowire arrays were prepared under high temperature and low pressure using CeCl3 as cerium source, ethylborane as boron source and carbon cloth as substrate. Different from previous reports, the nanowires in this paper are deposited on flexible and excellent carbon cloth. These results are expected to be widely used in flexible electronic display devices in the future. The samples were analyzed by X-ray powder diffractometer, Raman spectroscopy, field emission scanning electron microscopy (SEM), transmission electron microscope (TEM), high resolution transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), etc. The results show that there is a large area of nanowires deposited on the substrate, the length is about 10 渭 m and the diameter is about 100 nm, which grows along the direction of [100]. The results of the electron emission are being further tested. Thirdly, using ethylborane as boron source and methane as carbon source, a large number of boron carbide (BXCyB) nanowires and nanowire arrays were successfully synthesized. The results showed that: X-ray powder diffractometer, Raman spectroscopy, field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS). The synthesized sample is boron carbide low dimensional material. The results of field emission measurements show that the electron emission characteristics of boron carbide are excellent, and that the electron transport of single nanocrystalline material shows good conductivity. The photoelectric detection characteristics and further physicochemical characterization of boron carbide are being carried out, and good properties are expected.
【学位授予单位】：信阳师范学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;TQ128.1

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