杂原子掺杂碳材料的合成及其电化学性能研究
发布时间：2018-08-24 13:58
【摘要】：异质原子掺杂碳材料在电化学储能领域的应用研究与日俱增,这主要是由于掺杂异质原子后可在碳晶格引入更多的缺陷点位及增强电子传输特性,从而显著提升其电化学性能。例如氮掺杂进入石墨的晶格结构后可形成石墨型氮及吡咯、吡啶型氮,不仅可以提高纳米碳材料的表面化学活性,还可对其电子结构进行调节。近年来,除了氮,磷元素的掺杂也引起了越来越多的关注。由于磷的电负性低于碳的电负性,且给电子能力远强于碳,故磷元素掺杂的碳材料的电化学活性得到很大的提升。然而,目前为止,合成异质原子掺杂碳材料的方法依然非常有挑战性,亟待开发出简单的新方法。本文中,我们通过一系列方法合成了异质原子掺杂碳材料,并系统研究了异质原子的掺杂对材料电化学性质的影响,具体研究内容总结如下:(1)氮掺杂石墨烯的合成及其钠离子电池性能研究。1、通过在不同温度下热解中间相沥青及双氰胺,合成了氮掺杂石墨烯,其中中间相沥青为碳源,双氰胺为氮源以及模板。2、通过Hummers法合成氧化石墨,并在不同气氛下高温还原合成氮掺杂还原氧化石墨烯。两种方案合成方法简单、绿色环保,无需表面活性剂以及有毒的有机溶剂。得到的氮掺杂石墨烯由于其独特的褶皱结构、大的比表面积及良好的离子电子传导性能,在钠离子电池方面展现出较高的可逆容量、良好的循环稳定性,是非常有前景的钠离子电池负极材料。(2)磷掺杂石墨烯的合成及其钠离子电池性能研究。我们利用氧化石墨作为基体材料,三苯基磷作为磷源,超声混合后在高温下对氧化石墨作还原处理,制备出了磷氧共掺杂的还原氧化石墨烯,并且表现出优异的储钠性能。良好的电化学性能亦是得益于该电极材料不仅具有大的比表面积及褶皱状结构,而且还受益于磷原子掺杂之后石墨烯材料的电导率提高及其层间距变大等协同效应的影响。
[Abstract]:The application of heteroatom-doped carbon materials in the field of electrochemical energy storage is increasing day by day. This is mainly due to the introduction of more defects in the carbon lattice and the enhancement of electron transport characteristics after doping the heterogeneous atoms, which significantly improves its electrochemical performance. For example, nitrogen doping into the lattice structure of graphite can form graphite-type nitrogen and pyrrole, pyridine-type nitrogen, which can not only improve the surface chemical activity of nano-carbon materials, but also adjust its electronic structure. In recent years, in addition to nitrogen, phosphorus doping has also attracted more and more attention. Because the electronegativity of phosphorus is lower than that of carbon, and the electron ability is much stronger than that of carbon, the electrochemical activity of carbon doped with phosphorus is greatly improved. However, so far, the method of synthesizing heterogeneous atom doped carbon materials is still very challenging, and a new simple method is urgently needed to be developed. In this paper, we synthesized heterogeneous atom doped carbon material by a series of methods, and systematically studied the influence of heterogeneous atom doping on the electrochemical properties of the material. The specific research contents are summarized as follows: (1) the synthesis of nitrogen-doped graphene and the performance of sodium ion battery. 1. Nitrogen doped graphene was synthesized by pyrolysis of mesophase pitch and dicyandiamide at different temperatures, and its mesophase pitch was used as carbon source. Graphite oxide was synthesized by Hummers method with dicyandiamide as nitrogen source and template. The two methods are simple, green, no surfactant and toxic organic solvent. Because of its unique fold structure, large specific surface area and good ionic electron conductivity, the nitrogen-doped graphene shows high reversible capacity and good cycling stability in sodium ion batteries. It is a promising anode material for sodium ion batteries. (2) Synthesis of phosphate-doped graphene and study on the performance of sodium ion batteries. In this paper, graphite oxide was used as matrix material, triphenyl phosphorus as phosphorus source. After ultrasonic mixing, graphite oxide was reduced at high temperature to prepare reductive graphene, which was co-doped with phosphorus and oxygen, and showed excellent sodium storage properties. The good electrochemical performance is also due to not only the large specific surface area and fold structure of the electrode, but also the synergistic effects such as the increase of the conductivity and the increase of the interlayer spacing of the graphene materials doped with phosphorus atoms.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ127.11;TM912
本文编号：2201035
[Abstract]:The application of heteroatom-doped carbon materials in the field of electrochemical energy storage is increasing day by day. This is mainly due to the introduction of more defects in the carbon lattice and the enhancement of electron transport characteristics after doping the heterogeneous atoms, which significantly improves its electrochemical performance. For example, nitrogen doping into the lattice structure of graphite can form graphite-type nitrogen and pyrrole, pyridine-type nitrogen, which can not only improve the surface chemical activity of nano-carbon materials, but also adjust its electronic structure. In recent years, in addition to nitrogen, phosphorus doping has also attracted more and more attention. Because the electronegativity of phosphorus is lower than that of carbon, and the electron ability is much stronger than that of carbon, the electrochemical activity of carbon doped with phosphorus is greatly improved. However, so far, the method of synthesizing heterogeneous atom doped carbon materials is still very challenging, and a new simple method is urgently needed to be developed. In this paper, we synthesized heterogeneous atom doped carbon material by a series of methods, and systematically studied the influence of heterogeneous atom doping on the electrochemical properties of the material. The specific research contents are summarized as follows: (1) the synthesis of nitrogen-doped graphene and the performance of sodium ion battery. 1. Nitrogen doped graphene was synthesized by pyrolysis of mesophase pitch and dicyandiamide at different temperatures, and its mesophase pitch was used as carbon source. Graphite oxide was synthesized by Hummers method with dicyandiamide as nitrogen source and template. The two methods are simple, green, no surfactant and toxic organic solvent. Because of its unique fold structure, large specific surface area and good ionic electron conductivity, the nitrogen-doped graphene shows high reversible capacity and good cycling stability in sodium ion batteries. It is a promising anode material for sodium ion batteries. (2) Synthesis of phosphate-doped graphene and study on the performance of sodium ion batteries. In this paper, graphite oxide was used as matrix material, triphenyl phosphorus as phosphorus source. After ultrasonic mixing, graphite oxide was reduced at high temperature to prepare reductive graphene, which was co-doped with phosphorus and oxygen, and showed excellent sodium storage properties. The good electrochemical performance is also due to not only the large specific surface area and fold structure of the electrode, but also the synergistic effects such as the increase of the conductivity and the increase of the interlayer spacing of the graphene materials doped with phosphorus atoms.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ127.11;TM912
【参考文献】
相关期刊论文 前1条
1 陈旭;何大平;木士春;;掺氮石墨烯研究[J];化学进展;2013年08期
，本文编号：2201035
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