碳纳米材料的可控制备及场发射性能研究
发布时间：2018-09-11 07:09
【摘要】：碳纳米材料具有多样的结构、优异的物理和化学性质,近年来引起了广泛的关注。其中,石墨烯和碳纳米管由于独特的结构和优异的性能,已经成为了各个领域的研究热点,其中的一个潜在应用就是作为场发射电子源。人们针对两种材料的场致发射开展了大量的研究工作,并取得了不错的进展。本文针对石墨烯在场致发射应用中出现的不足,使用不同方法制备了性能较好的石墨烯,并充分地突出了石墨烯作为场发射材料的结构优势。除此之外,还探索并优化了碳纳米管的制备条件,同时提高了碳纳米管的场发射性能。主要的研究内容如下:使用电泳沉积的方法在含有微孔的图案化不锈钢(SUS304)基底上制备了石墨烯发射体,并使用一定的方式进行表面处理。这种三维石墨烯发射体的微孔内含有较多直立排布的锋利边缘,其场发射性能相比平面基底上的石墨烯有了显著的提高,不仅具有更低的开启和阈值电场,其发射电流密度也提高了近十倍。这种设计为基于层状结构的冷阴极提供了更多的可能。使用等离子体增强化学气相沉积方法在不同种类基底上成功制备了石墨烯墙,并深入研究了不同的生长参数对石墨烯墙场发射性能的影响。石墨烯墙的形貌及微观结构也可以通过不同的生长参数进行调节。具有开放边缘的直立石墨烯墙表现出了很好的场发射性能。场发射测试之后尽管石墨烯墙的形貌改变较大,其场发射性能并没有明显衰减。使用等离子体增强化学气相沉积技术在不同尺寸的六边形图案化Si基底上成功制备了直立碳纳米管阵列。同时也在其他基底上进行了制备,并通过改变不同的实验参数包括催化剂种类、过渡层以及H2/C2H2通入比例等对碳纳米管生长和场发射性能进行了优化。碳纳米管发射体表现出了优异的场发射性能,不仅具有较大的发射电流密度还具有很好的发射稳定性。
[Abstract]:Carbon nanomaterials have attracted wide attention in recent years because of their diverse structures and excellent physical and chemical properties. Among them, graphene and carbon nanotubes (CNTs) have become a hot research field due to their unique structure and excellent properties. One of the potential applications is as a field emission electron source. A great deal of research work has been done on the field emission of two kinds of materials, and good progress has been made. In this paper, graphene with good properties has been prepared by different methods in allusion to the shortcomings in the field emission application of graphene, and the structural advantages of graphene as a field emission material have been fully highlighted. In addition, the preparation conditions of carbon nanotubes were explored and optimized, and the field emission properties of carbon nanotubes were improved. The main research contents are as follows: graphene emitters were prepared on patterned stainless steel (SUS304) substrates containing micropores by electrophoretic deposition and treated in a certain way. The three dimensional graphene emitters have many sharp edges arranged vertically in their micropores. The field emission performance of the three dimensional graphene emitters is significantly improved compared with that of the graphene on the planar substrate, and not only has a lower opening and threshold electric field. The emission current density has also increased by nearly ten times. This design provides more possibilities for cold cathode based on layered structure. Graphene walls were successfully prepared on different substrates by plasma enhanced chemical vapor deposition. The effects of different growth parameters on the field emission properties of graphene walls were studied. The morphology and microstructure of graphene wall can also be adjusted by different growth parameters. The vertical graphene wall with open edge exhibits good field emission performance. After field emission testing, the field emission properties of graphene wall did not decrease significantly, although the morphology of the wall changed greatly. The vertical carbon nanotube arrays were successfully fabricated on hexagonal patterned Si substrates by plasma enhanced chemical vapor deposition. At the same time, the growth and field emission properties of CNTs were optimized by changing different experimental parameters such as catalyst type, transition layer and H2/C2H2 input ratio. Carbon nanotubes (CNTs) emitters exhibit excellent field emission properties, not only with high emission current density, but also with good emission stability.
【学位授予单位】：燕山大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O613.71
本文编号：2235975
[Abstract]:Carbon nanomaterials have attracted wide attention in recent years because of their diverse structures and excellent physical and chemical properties. Among them, graphene and carbon nanotubes (CNTs) have become a hot research field due to their unique structure and excellent properties. One of the potential applications is as a field emission electron source. A great deal of research work has been done on the field emission of two kinds of materials, and good progress has been made. In this paper, graphene with good properties has been prepared by different methods in allusion to the shortcomings in the field emission application of graphene, and the structural advantages of graphene as a field emission material have been fully highlighted. In addition, the preparation conditions of carbon nanotubes were explored and optimized, and the field emission properties of carbon nanotubes were improved. The main research contents are as follows: graphene emitters were prepared on patterned stainless steel (SUS304) substrates containing micropores by electrophoretic deposition and treated in a certain way. The three dimensional graphene emitters have many sharp edges arranged vertically in their micropores. The field emission performance of the three dimensional graphene emitters is significantly improved compared with that of the graphene on the planar substrate, and not only has a lower opening and threshold electric field. The emission current density has also increased by nearly ten times. This design provides more possibilities for cold cathode based on layered structure. Graphene walls were successfully prepared on different substrates by plasma enhanced chemical vapor deposition. The effects of different growth parameters on the field emission properties of graphene walls were studied. The morphology and microstructure of graphene wall can also be adjusted by different growth parameters. The vertical graphene wall with open edge exhibits good field emission performance. After field emission testing, the field emission properties of graphene wall did not decrease significantly, although the morphology of the wall changed greatly. The vertical carbon nanotube arrays were successfully fabricated on hexagonal patterned Si substrates by plasma enhanced chemical vapor deposition. At the same time, the growth and field emission properties of CNTs were optimized by changing different experimental parameters such as catalyst type, transition layer and H2/C2H2 input ratio. Carbon nanotubes (CNTs) emitters exhibit excellent field emission properties, not only with high emission current density, but also with good emission stability.
【学位授予单位】：燕山大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O613.71
【参考文献】
相关期刊论文 前2条
1 张滨;孙玉珍;王文皓;;关于用UPS测量功函数[J];物理测试;2007年04期
2 王如志,王波,严辉;场电子发射研究现状及理论概述[J];物理;2002年02期
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