基于复合盐—碱法制备硒化物半导体纳米材料及其相关性能研究

发布时间：2018-10-25 20:32

【摘要】：Zn Se,Ni Se2,Pb Se是三种重要的硒化物半导体光电材料,有一系列优异的物理和化学性能,并且都属于直接带隙半导体,在光电子纳米器件和医学领域有广阔的应用前景。因此,本文采用一种特殊的溶剂热法系统地摸索并且成功掌握了这三种硒化物微纳米材料的合成技术,实现对晶体结构、维度、微观形貌的调控,并深入研究了他们的光学性质,主要研究内容包括:利用复合熔融盐-碱媒介(SACM)法成功制备了片状的Zn Se微纳米材料,所谓复合熔融盐-碱媒介法就是采用熔融的盐和碱作为反应溶剂代替传统的水或者有机溶剂,在低温条件下通过化学反应合成纳米材料。本实验研究了不同影响因素对产物的形貌和尺寸的影响,并且提出了Zn Se在复合盐-碱体系中的生长机理。通过产物的紫外光谱算出它的能带带隙大约为3.25e V,故我们选用紫外光进行了一系列的光催化降解实验。实验表明,在低功率紫外光照条件下,样品的光催化降解效率最高可达到87.32%。在复合熔融盐-碱媒介(SACM)法的基础上,我们又成功合成了两种不同元素比例的八面体结构的硒化镍(Ni Se2/Ni0.85Se)纳米材料。实验也探讨了反应时间和水量对产物形貌的变化,并采用XRD、EDS和SEM分析。对此我们也提出了产物的形成机理以及产物发生转变的过程分析。通过两种不同硒化镍的紫外光谱计算它们的能带带隙大约为1.47e V和1.75e V。本实验还研究了Ni Se2纳米八面体在不同的介质中的电化学性能,测定了其CV曲线。实验表明,Ni Se2在碱性的Na OH溶液里的电化学活性比在中性的KNO3溶液里要好而且CV曲线重复性良好,所以产物具有很好的重复利用性。Pb Se纳米粒子是典型的窄禁带宽度(Eg=0.27 e V at 300 K)的IV-VI族半导体纳米晶材料。我们利用复合熔融盐媒介(CMS)法和复合熔融盐-碱媒介(SACM)法成功合成了两种不同形貌的Pb Se纳米材料。通过SEM和TEM分析,我们提出了Pb Se在不同体系中的生长机理,探讨了立方结构Pb Se形成的原因。
[Abstract]:Zn Se,Ni Se2,Pb Se is one of the three important selenide semiconductor optoelectronic materials. It has a series of excellent physical and chemical properties and belongs to direct band gap semiconductor. It has a broad application prospect in the field of photoelectron nanodevices and medicine. Therefore, in this paper, a special solvothermal method is used to explore and successfully master the synthesis technology of these three kinds of selenides, which can control the crystal structure, dimension and morphology. Their optical properties were studied in depth. The main research contents were as follows: the flake Zn Se micro-nano materials were successfully prepared by the (SACM) method of composite molten salt-alkali medium. The so-called complex melt salt-alkali medium method is to use molten salt and alkali as reaction solvent instead of traditional water or organic solvent to synthesize nanomaterials by chemical reaction at low temperature. The effects of different factors on the morphology and size of the product were studied, and the growth mechanism of Zn Se in the complex salt-alkali system was proposed. The band gap of the product was estimated to be about 3.25e V by UV spectra, so we selected ultraviolet light for a series of photocatalytic degradation experiments. The experimental results show that the photocatalytic degradation efficiency of the sample is up to 87.32 kW under low power UV irradiation. On the basis of (SACM) method of complex molten salt and alkali medium, two kinds of Ni Se2/Ni0.85Se nanomaterials with octahedron structure with different proportion of elements have been successfully synthesized. The changes of reaction time and amount of water on the morphology of the product were also investigated and analyzed by XRD,EDS and SEM. We also put forward the formation mechanism of the product and the process analysis of the product transformation. The band gaps of two kinds of nickel selenide are estimated to be 1.47 EV and 1.75 EV by UV spectra. The electrochemical properties of Ni Se2 nanooctahedron in different media were also studied and its CV curves were measured. The results show that the electrochemical activity of Ni Se2 in alkaline Na OH solution is better than that in neutral KNO3 solution, and the CV curve is reproducible. So the. Pb Se nanoparticles with good reusability are typical IV-VI semiconductor nanocrystalline materials with narrow band gap (Eg=0.27 e V at 300K). We have successfully synthesized two kinds of Pb Se nanomaterials with different morphologies by (CMS) method and (SACM) method. Through the analysis of SEM and TEM, we put forward the growth mechanism of Pb Se in different systems, and discussed the reason of the formation of cubic Pb Se.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1

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