石墨烯复合物制备及其光电性能研究

发布时间：2018-01-26 21:05

本文关键词： 石墨烯硅锥硒化锌合成光电性能　出处：《东华大学》2015年硕士论文　论文类型：学位论文

【摘要】：自2004年发现石墨烯以来，石墨烯及其复合纳米材料在材料科学、纳米电子学等领域引起了人们的极大关注。石墨烯是世界上最薄的二维材料，并具有独特的电学性能、良好的稳定性和高的长径比，这使其成为良好的场发射材料。但石墨烯存在的一些缺点也是我们不能忽视的，比如其非刚性结构导致容易聚合。所以科研人员花费了大量的精力来研究以石墨烯为基底的复合材料，通过与其他材料的复合，克服自身缺陷，发挥自身的优势。本论文中，分两部分分别研究石墨烯/ZnSe复合物、石墨烯/硅锥复合物的制备及其光电特性。 1.我们利用水热法在石墨烯薄膜表面生长出ZnSe微米球，形成石墨烯/ZnSe复合材料并研究其光电性能。实验中我们发现不同浓度的EDTA对复合物的形貌及光学性能都产生较大的影响。当EDTA浓度为0.30M时，大量像仙人球一样的ZnSe微米球生长在石墨烯薄膜表面，并且其平均直径大约为10μm；当EDTA浓度为0.45M时，ZnSe微米球的形状像蜂巢一样，而不是长成仙人球状。通过XRD图谱，我们可以得出形成的ZnSe微米球为立方闪锌矿结构。对复合物的光学性能研究发现该复合物在225nm处有最大的紫外可见吸收光；在468nm处存在最强的近带边发射峰。 2.我们通过LP-CVD法在铜箔表面制备出了大面积石墨烯薄膜，，并用离子束轰击方法制备了硅纳米锥阵列，最后分别将石墨烯薄膜转移到硅晶圆和硅纳米锥阵列表面并研究其场发射性能。材料的场增强因子与发射体形状和几何参数相关。由于石墨烯薄膜的曲率与硅锥尖端的曲率是一致的，因此它们具有相同的增强因子。据此得出随着硅纳米锥曲率的增加，覆盖其上的石墨烯的功函数降低，并改善石墨烯场发射的性能。研究结果表明，石墨烯薄膜及其复合纳米材料有望在可折叠柔性光电器件等方面得到广泛应用。
[Abstract]:Since the discovery of graphene in 2004, graphene and its composite nanomaterials have attracted great attention in materials science, nanoelectronics and other fields. Graphene is the thinnest two-dimensional material in the world. It has unique electrical properties, good stability and high aspect ratio, which makes it a good field emission material, but some shortcomings of graphene can not be ignored. For example, its non-rigid structure makes it easy to polymerize. Therefore, researchers have devoted a lot of effort to studying graphene based composites, which can overcome their own defects by combining with other materials. In this thesis, the preparation and photoelectric properties of graphene / ZnSe composites, graphene / silicon cone composites and graphene / ZnSe composites are studied in two parts. 1. ZnSe microspheres were grown on the surface of graphene film by hydrothermal method. Graphene / ZnSe composites were formed and their optoelectronic properties were studied. We found that the morphology and optical properties of graphene / ZnSe composites were greatly affected by different concentrations of EDTA. When the concentration of EDTA was 0. 30m. A large number of ZnSe microspheres like cactus grow on the surface of graphene film, and their average diameter is about 10 渭 m. When the concentration of EDTA is 0. 45m, the microspheres are shaped like honeycomb instead of growing into cactus. Through the XRD pattern. It is found that the ZnSe microspheres are cubic sphalerite structure. The optical properties of the composite show that the composite has the largest UV visible absorption at 225 nm. There is the strongest near band emission peak at 468 nm. 2. Large area graphene thin films were prepared on copper foil by LP-CVD method, and silicon nanocone arrays were prepared by ion beam bombardment. Finally, the graphene film was transferred to the surface of silicon crystal circle and silicon nanocone array and its field emission properties were studied. The field enhancement factor of the material is related to the shape and geometric parameters of the emitter. Because of the curvature of graphene film and the silicon cone, the field enhancement factor of the material is related to the shape and geometry of the emitter. The curvature of the tip is the same. Therefore, they have the same enhancement factors. It is concluded that with the increase of the curvature of silicon nanometers, the work function of graphene coated on it decreases and the field emission performance of graphene is improved. The results show that graphene thin films and composite nanomaterials are expected to be widely used in folding flexible optoelectronic devices.
【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O613.71

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