高温溶剂法制备半导体纳米晶及其发光调制和形貌控制研究
发布时间：2019-05-18 20:40
【摘要】： 纳米粒子是纳米技术研究中的一个基本单元,它给人们提供了研究与尺寸相关特性的合适对象,因此,纳米粒子在纳米材料中也占有特别重要的地位,同时在能源、医药卫生、电子和计算机、环境保护、新材料设计等领域也都有着非常广泛的应用前景。近年来针对半导体纳米粒子(纳米晶)的制备方法、合成机理的研究一直是科研工作者所关注的领域,尤其以利用高温溶剂法制备半导体纳米晶所开展的研究工作为代表。目前合成纳米晶材料在前驱体的使用上有相对固定的选择,如在涉及CdSe纳米晶的制备中,除了早期毒性较大的有机金属盐(比如二甲基镉)外,大都选择氧化镉作为镉的前驱物,其它的离子型化合物则很少涉及;在含汞近红外发射半导体纳米晶的制备上,由于其高温下不稳定的特点,室温合成路线就具有很大的优势,但相应的研究报道却很少;在其它诸如金属氧化物半导体纳米晶的制备过程中的一些重要参数如介质的选择、反应温度的调节、反应时间的控制以及表面活性剂的运用对反应的结果都具有直接而重要的影响,如何通过相关实验的设计,深入理解其中相关参数的作用,从而更加有效地开展纳米晶的可控及规模合成也是目前合成、制备研究中亟待解决的问题。 本论文即以上述问题为出发点,在高温溶剂法的基础上主要开展相关的合成研究及部分性质表征工作,主要包括以下内容: (1)选用离子型镉源作前驱体成功的在较低的反应温度下制备了ZnSe/CdSe复合结构纳米晶,并对其发光机理进行了深入的探讨。在此基础上,结合当前“绿色”环保的要求,开展了低毒、高效、低能耗的合成方法研究,针对目前广泛采用的含膦化合物的合成方法,创新性的采用无膦化合物的合成路线制备了较高质量的ZnSe纳米晶并开展了基于宽带隙ZnSe半导体纳米晶的过渡族元素中心掺杂体系ZnSe:Cu/ZnSe/ZnS复合结构纳米晶的绿色合成制备。通过Cu~(2+)的引入,实现了对ZnSe纳米晶的荧光发射的有效调节。适当厚度的ZnS壳层则可以很好的钝化粒子表面,从而提高荧光发射强度;通过采用不同粒径的ZnSe纳米晶为核,该复合结构纳米晶的发射波长可在480~520 nm的范围内实现连续调节。 (2)探索了室温环境下高质量近红外纳米晶的制备。在CdTe纳米晶结构控制合成的基础上,采用室温离子交换的间接制备方法实现了HgCdTe近红外纳米晶的制备,并进一步实现了具有近红外发射的HgTe纳米晶的室温合成。 (3)利用高温热解等方法制备了一系列的金属氧化物等化合物,在探索新合成方法的同时,着重探讨了反应温度、复合表面活性剂的使用以及前驱物的选择对产物结构、成分和性质的影响,并对其机理也进行了相应的探讨。以上工作的开展为下一步开展基于纳米晶的器件研究奠定了基础。
[Abstract]:Nanoparticles are a basic unit in the research of nanotechnology, which provides a suitable object for people to study the characteristics related to size. Therefore, nanoparticles also play a particularly important role in nanomaterials, at the same time in energy, medicine and health. Electronic and computer, environmental protection, new material design and other fields also have a very wide range of application prospects. In recent years, the research on the synthesis mechanism of semiconductor nanoparticles (nanocrystals) has been a field of concern to researchers, especially the research work carried out in the preparation of semiconductor nanoparticles by high temperature solvent method. At present, synthetic nanocrystal materials have a relatively fixed choice in the use of precursors, such as in the preparation of CdSe nanocrystals, in addition to the early toxic organometallic salt (such as dimethyl cadmium), Most of them chose cadmium oxide as the precursor of cadmium, while other ionic compounds were rarely involved. In the preparation of near infrared emission semiconductor nanocrystals containing mercury, due to its unstable characteristics at high temperature, the synthesis route at room temperature has great advantages, but the corresponding research reports are very few. Some important parameters in the preparation of other metal oxide semiconductor nanocrystals, such as the selection of media and the regulation of reaction temperature, The control of reaction time and the use of surfactants have a direct and important influence on the results of the reaction. How to deeply understand the role of the relevant parameters through the design of related experiments. Therefore, more effective controllable and scale synthesis of nanocrystals is also an urgent problem to be solved in the research of preparation. Based on the above problems, this paper mainly studies the synthesis and characterization of some properties on the basis of high temperature solvent method. The main contents are as follows: (1) ZnSe/CdSe composite structure nanocrystals were successfully prepared by using ion cadmium source as precursor at low reaction temperature, and its luminous mechanism was discussed in detail. On this basis, combined with the current requirements of "green" environmental protection, the synthesis methods of low toxicity, high efficiency and low energy consumption were studied, and the synthesis methods of phosphine compounds, which were widely used at present, were studied. High quality ZnSe nanocrystals were prepared by innovative synthesis of phosphine-free compounds, and ZnSe:Cu/ZnSe/ZnS composite structure nanocrystals of transition group element center doping system based on broadband gap ZnSe semiconductor nanocrystals were carried out. Green synthesis of. Through the introduction of Cu~ (2), the fluorescence emission of ZnSe nanocrystals is adjusted effectively. The proper thickness of ZnS shell can passivate the surface of particles, so as to improve the fluorescence emission intensity. By using ZnSe nanocrystals with different particle sizes as cores, the emission wavelength of the composite structure nanocrystals can be adjusted continuously in the range of 480 nm. (2) the preparation of high quality near infrared nanocrystals at room temperature was investigated. On the basis of controlled synthesis of CdTe nanocrystals, HgCdTe near-infrared nanocrystals were prepared by ion exchange at room temperature, and HgTe nanocrystals with near-infrared emission were further synthesized at room temperature. (3) A series of metal oxides and other compounds were prepared by pyrolysis at high temperature. while exploring the new synthesis methods, the reaction temperature, the use of composite surfactants and the selection of precursors on the structure of the products were discussed. The effects of composition and properties were discussed, and the mechanism was also discussed. The above work lays a foundation for the next step of device research based on nanocrystals.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2010
【分类号】：TB383.1
本文编号：2480320
[Abstract]:Nanoparticles are a basic unit in the research of nanotechnology, which provides a suitable object for people to study the characteristics related to size. Therefore, nanoparticles also play a particularly important role in nanomaterials, at the same time in energy, medicine and health. Electronic and computer, environmental protection, new material design and other fields also have a very wide range of application prospects. In recent years, the research on the synthesis mechanism of semiconductor nanoparticles (nanocrystals) has been a field of concern to researchers, especially the research work carried out in the preparation of semiconductor nanoparticles by high temperature solvent method. At present, synthetic nanocrystal materials have a relatively fixed choice in the use of precursors, such as in the preparation of CdSe nanocrystals, in addition to the early toxic organometallic salt (such as dimethyl cadmium), Most of them chose cadmium oxide as the precursor of cadmium, while other ionic compounds were rarely involved. In the preparation of near infrared emission semiconductor nanocrystals containing mercury, due to its unstable characteristics at high temperature, the synthesis route at room temperature has great advantages, but the corresponding research reports are very few. Some important parameters in the preparation of other metal oxide semiconductor nanocrystals, such as the selection of media and the regulation of reaction temperature, The control of reaction time and the use of surfactants have a direct and important influence on the results of the reaction. How to deeply understand the role of the relevant parameters through the design of related experiments. Therefore, more effective controllable and scale synthesis of nanocrystals is also an urgent problem to be solved in the research of preparation. Based on the above problems, this paper mainly studies the synthesis and characterization of some properties on the basis of high temperature solvent method. The main contents are as follows: (1) ZnSe/CdSe composite structure nanocrystals were successfully prepared by using ion cadmium source as precursor at low reaction temperature, and its luminous mechanism was discussed in detail. On this basis, combined with the current requirements of "green" environmental protection, the synthesis methods of low toxicity, high efficiency and low energy consumption were studied, and the synthesis methods of phosphine compounds, which were widely used at present, were studied. High quality ZnSe nanocrystals were prepared by innovative synthesis of phosphine-free compounds, and ZnSe:Cu/ZnSe/ZnS composite structure nanocrystals of transition group element center doping system based on broadband gap ZnSe semiconductor nanocrystals were carried out. Green synthesis of. Through the introduction of Cu~ (2), the fluorescence emission of ZnSe nanocrystals is adjusted effectively. The proper thickness of ZnS shell can passivate the surface of particles, so as to improve the fluorescence emission intensity. By using ZnSe nanocrystals with different particle sizes as cores, the emission wavelength of the composite structure nanocrystals can be adjusted continuously in the range of 480 nm. (2) the preparation of high quality near infrared nanocrystals at room temperature was investigated. On the basis of controlled synthesis of CdTe nanocrystals, HgCdTe near-infrared nanocrystals were prepared by ion exchange at room temperature, and HgTe nanocrystals with near-infrared emission were further synthesized at room temperature. (3) A series of metal oxides and other compounds were prepared by pyrolysis at high temperature. while exploring the new synthesis methods, the reaction temperature, the use of composite surfactants and the selection of precursors on the structure of the products were discussed. The effects of composition and properties were discussed, and the mechanism was also discussed. The above work lays a foundation for the next step of device research based on nanocrystals.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2010
【分类号】：TB383.1
【引证文献】
中国博士学位论文全文数据库 前1条
1 王美平;CdTe及其核壳结构纳米晶的水相合成与荧光性能研究[D];成都理工大学;2012年
，本文编号：2480320
本文链接：https://www.wllwen.com/shekelunwen/minzhuminquanlunwen/2480320.html
