低维Ag纳米结构的可控制备及应用研究

发布时间：2018-05-01 04:30

本文选题：银纳米结构 + 合成方法　；参考：《华北电力大学(北京)》2016年博士论文

【摘要】：随着化石能源的日渐枯竭,如何解决能源紧缺的问题已经成为全球共同关注的热点,深入开发应用低碳、绿色、环保、低成本的新材料是解决能源危机及环境问题的重要举措。银纳米材料作为重要的金属纳米材料之一,因其优异的光、电、磁、热等性质,使其在催化、电子、光伏发电等领域具有巨大的潜在应用价值。但目前对于低维银纳米材料的可控制备工艺和修饰改性方面仍然存在一些问题,在很大程度阻碍和限制了低维银纳米材料的发展和应用。基于此,本论文阐述了不同形貌低维银纳米结构的制备方法,研究了不同形貌银纳米结构的生长机理及影响因素。进一步以合成的银纳米材料为基础,一方面研究了磁控溅射法和超声波法对银纳米线的形貌调控,以及无序银纳米线的定向排列。另一方面研究了银纳米颗粒和银纳米线辅助硅刻蚀的内在机理。此外,合成了Ag-Ag2S和Ag2S-NiO复合纳米材料,并对其光催化性能进行了研究。具体研究工作包括：利用水热合成法制备了不同形貌的银纳米结构。通过调节PVP和Na2S的用量合成了形貌可控的银纳米颗粒、银纳米立方体及银纳米多面体。利用银晶核生长的方法制备了一种内部包裹有团聚银纳米颗粒的球形特殊结构。此外,研究了磁控溅射法在硅片表面制备了半球形、椭球状、大面积聚集不规则形状银纳米颗粒,阐述了颗粒尺寸与溅射时间的关系。利用水热法制备了具有较高长径比的银纳米线,并以此为基础,一方面研究了磁控溅射法可控制备了具有丰富“刺状”突起的银纳米线结构,讨论了溅射时间与修饰程度之间的关系,以及修饰后银纳米线的SERS性能。另一方面研究了超声波在液体环境中对银纳米线造成的弯折和折断,分析了不同直径银纳米线弯折及断裂处银原子排列情况,进一步研究了超声后银纳米线的吸收光谱。此外,对分散在挥发性溶剂里无序的银纳米线在铺展过程中实现大面积定向排列进行了研究,分析了液体微流产生的冲击力和银纳米线与衬底之间的粘附力以及分散液的快速挥发对银纳米线定向的影响,同时提出了定向后银纳米线的转移方法。以磁控溅射制备的银纳米颗粒和水热合成的银纳米线为基础,研究了银纳米颗粒与银纳米线辅助刻蚀硅过程。在激光照射条件下,银纳米颗粒产生的LSPR效应在硅表面形成了“弹坑状”刻蚀结构,基于麦氏理论和电化学理论分析了刻蚀过程与刻蚀机理,阐述了银纳米颗粒的散射半径与“弹坑状”结构的开口尺寸之间的关系。另一方面研究了银纳米线辅助硅刻蚀过程,论述了银纳米线与硅基底表面的接触程度对刻蚀结构由光滑刻蚀槽到粗糙的多孔硅刻蚀槽转变过程的影响,揭示了银纳米线辅助硅刻蚀过程的刻蚀机理。合成了Ag-Ag2S复合纳米结构,阐述了链状Ag-Ag2S复合结构和Ag-Ag2S复合纳米颗粒的形成过程及结构特点。此外,利用Ag2S和NiO通过水热反应制备了Ag2S-NiO复合纳米结构,阐述了该复合结构的结构特点。可见光光催化性能研究结果表明这两种复合纳米结构均具有良好的可见光光催化性能。
[Abstract]:With the depletion of fossil energy, how to solve the problem of energy shortage has become a hot topic of common concern in the world. Developing new materials with low carbon, green, environmental protection and low cost is an important measure to solve the energy crisis and environmental problems. Silver nanomaterials are one of the most important metal nanomaterials, because of their excellent light and electricity. Magnetic, thermal and other properties have great potential applications in the fields of catalytic, electronic and photovoltaic power generation. However, there are still some problems in the controllable preparation and modification of low dimensional silver nanomaterials, which hinders and restricts the development and application of low dimensional silver nanomaterials to a great extent. Based on this, this paper describes the development and application of low dimensional silver nanomaterials. The growth mechanism and influence factors of different morphologies of silver nanostructures were studied with different morphologies. On the basis of the synthesized silver nanomaterials, the morphology and regulation of the silver nanowires and the directional arrangement of the disordered silver nanowires were studied on the basis of the synthesized silver nanomaterials. On the other hand, the study of the disordered silver nanowires was studied. The intrinsic mechanism of silver nanoparticles and silver nanowires assisted silicon etching was made. In addition, Ag-Ag2S and Ag2S-NiO composite nanomaterials were synthesized and their photocatalytic properties were studied. The specific research work included the preparation of silver nanostructures with different morphologies by hydrothermal synthesis. The morphologies were controlled by adjusting the amount of PVP and Na2S. Silver nanoparticles, silver nano cubes and silver nano polyhedron are used to prepare a special spherical structure containing agglomerated silver nanoparticles by the method of ArgentCrystal nuclear growth. In addition, the magnetron sputtering method is used to prepare the hemispherical, ellipsoid and large area irregular shape silver nanoparticles on the surface of the silicon wafer. The relationship between size and sputtering time. The silver nanowires with a high ratio of length to diameter were prepared by hydrothermal method. On the basis of this, the structure of silver nanowires with rich "spiny" protuberances could be controlled by magnetron sputtering. The relationship between the sputtering time and the degree of modification, and the SERS of the modified silver nanowires were discussed. On the other hand, the bending and breaking of the silver nanowires in the liquid environment were studied. The arrangement of silver atoms at the bending and fracture of the silver nanowires with different diameters was analyzed. The absorption spectrum of the silver nanowires after ultrasonic was further studied. In addition, the disordered silver nanowires dispersed in the volatile solvents were spread out in the spreading process. The effect of the impact force produced by the liquid micro flow and the adhesion between the silver nanowires and the substrate and the rapid volatilization of the dispersing liquid on the orientation of the silver nanowires are analyzed. At the same time, the transfer method of the silver nanowires after the orientation is put forward. The silver nanoparticles and the hydrothermal synthesis of silver prepared by the magnetically controlled splash are made. On the basis of nanowires, the process of etching silicon with silver nanowires and silver nanowires was studied. Under the condition of laser irradiation, the LSPR effect produced by silver nanoparticles formed a "crater like" etching structure on the silicon surface. The etching process and etching mechanism were analyzed based on the theory of Mai's theory and electrochemistry, and the scattering half of the silver nanoparticles was expounded. The relationship between the diameter and the opening size of the "crater like" structure was studied. On the other hand, the effect of the silver nanowires on the etching process was studied. The influence of the contact degree of the silver nanowires with the surface of the silicon substrate on the transformation process of the etching structure from the smooth etching slot to the rough porous silicon etching slot was discussed, and the etching process of the silver nanowires assisted silicon etching was revealed. The Ag-Ag2S composite nanostructure was synthesized. The formation process and structure characteristics of the chain like Ag-Ag2S composite structure and Ag-Ag2S composite nanoparticles were described. In addition, Ag2S-NiO composite nanostructures were prepared by hydrothermal reaction by Ag2S and NiO, and the structure characteristics of the composite structure were described. The results of the visible light photocatalytic properties were shown. These two composite nanostructures exhibit good photocatalytic properties under visible light.

【学位授予单位】：华北电力大学(北京)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TB383.1;TQ131.22

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