高温热解法制备氮掺杂石墨烯及其表征
发布时间：2018-08-17 13:14
【摘要】：石墨烯是一种二维结构的碳原子薄膜,因为它出色的性质和潜在的应用价值正在吸引着越来越多的科学关注。氮元素掺杂是一种有效改善石墨烯能带结构和性质的方法,对于拓展石墨烯的应用非常重要。本论文利用高温热解法成功制备氮掺杂石墨烯并对其进行了详细表征。主要内容如下:1、采用高温热解双氰胺和葡萄糖混合物的方法成功制备了高氮含量的掺杂石墨烯。测试结果显示,通过改变双氰胺和葡萄糖质量比可以实现对样品中氮原子掺杂浓度的有效调节:当两者质量比从5~20变化时,氮原子掺杂量从22.44 at%逐渐减少到17.77 at%。氮原子在石墨烯中共有三种形式,分别是吡啶型氮、吡咯型氮和石墨型氮。荧光测试结果表明,石墨型氮是导致样品荧光猝灭现象的主要原因,荧光猝灭率随着石墨型氮浓度的增大而增大。2、采用高温热解三聚氰胺和葡萄糖混合物的方法成功制备了高氮含量的掺杂石墨烯。测试结果显示,三聚氰胺和双氰胺一样,可以在氮掺杂石墨烯的形成过程中起到模板剂和氮源作用。通过改变三聚氰胺和葡萄糖质量比可以实现对样品中氮原子掺杂浓度的有效调节:当两者质量比从10~40变化时,氮原子掺杂量从21.26 at%逐渐减少到18.79 at%。和双氰胺相比,使用三聚氰胺更有优势:在两者和葡萄糖质量比相同的情况下,样品中氮掺杂浓度基本一致,但是使用三聚氰胺比使用双氰胺能够获得更高的产率。3、在三聚氰胺和葡萄糖质量比为20时,研究了热解温度对样品中氮掺杂浓度的影响。测试结果显示,通过改变热解温度可以实现对样品中的氮掺杂浓度的大范围调控,当热解温度从700℃升高到900℃度变化时,样品中氮掺杂浓度从33.32 at%逐渐减少到10.87 at%。三种氮原子热稳定性不同:吡啶型氮和吡咯型氮的热稳定性较差,浓度随着温度的升高而降低;石墨型氮的热稳定性较好,浓度在700℃到900℃范围内基本是保持不变。本论文研究结果显示,高温热解法是一种能够有效制备氮掺杂石墨烯方法,这将有利于促进石墨烯的进一步应用。
[Abstract]:Graphene is a two-dimensional structure of carbon atom film, because of its outstanding properties and potential applications are attracting more and more scientific attention. Nitrogen doping is an effective method to improve the energy band structure and properties of graphene, which is very important to expand the application of graphene. In this paper, nitrogen-doped graphene was prepared by high temperature pyrolysis and characterized in detail. The main contents are as follows: 1. High nitrogen doped graphene was prepared by pyrolysis of dicyandiamide and glucose mixture at high temperature. The results show that the concentration of nitrogen atom can be adjusted effectively by changing the mass ratio of dicyandiamide to glucose: when the mass ratio of the two changes from 5 to 20, the amount of nitrogen atom doping decreases gradually from 22.44 at% to 17.77 atg. There are three forms of nitrogen atoms in graphene, namely pyridine nitrogen, pyrrole nitrogen and graphite nitrogen. The fluorescence test results show that graphite-type nitrogen is the main cause of fluorescence quenching. The fluorescence quenching rate increased with the increase of the concentration of graphite-type nitrogen. High nitrogen doped graphene was prepared by pyrolysis of melamine and glucose mixture at high temperature. The results showed that melamine, like dicyandiamide, could act as a template and nitrogen source in the formation of nitrogen-doped graphene. By changing the mass ratio of melamine to glucose, the concentration of nitrogen atom in the sample can be adjusted effectively: when the mass ratio of the two changes from 10 to 40, the amount of nitrogen atom doping gradually decreases from 21.26 at% to 18.79 ataspects. Compared with dicyandiamide, melamine has more advantages: when the mass ratio of both and glucose is the same, the nitrogen doping concentration in the sample is basically the same. However, the yield of melamine was higher than that of dicyandiamide. The effect of pyrolysis temperature on the concentration of nitrogen doping in the sample was studied when the mass ratio of melamine to glucose was 20:00. The results show that the nitrogen doping concentration can be controlled in a wide range by changing the pyrolysis temperature. When the pyrolysis temperature increases from 700 鈩，
本文编号：2187746
[Abstract]:Graphene is a two-dimensional structure of carbon atom film, because of its outstanding properties and potential applications are attracting more and more scientific attention. Nitrogen doping is an effective method to improve the energy band structure and properties of graphene, which is very important to expand the application of graphene. In this paper, nitrogen-doped graphene was prepared by high temperature pyrolysis and characterized in detail. The main contents are as follows: 1. High nitrogen doped graphene was prepared by pyrolysis of dicyandiamide and glucose mixture at high temperature. The results show that the concentration of nitrogen atom can be adjusted effectively by changing the mass ratio of dicyandiamide to glucose: when the mass ratio of the two changes from 5 to 20, the amount of nitrogen atom doping decreases gradually from 22.44 at% to 17.77 atg. There are three forms of nitrogen atoms in graphene, namely pyridine nitrogen, pyrrole nitrogen and graphite nitrogen. The fluorescence test results show that graphite-type nitrogen is the main cause of fluorescence quenching. The fluorescence quenching rate increased with the increase of the concentration of graphite-type nitrogen. High nitrogen doped graphene was prepared by pyrolysis of melamine and glucose mixture at high temperature. The results showed that melamine, like dicyandiamide, could act as a template and nitrogen source in the formation of nitrogen-doped graphene. By changing the mass ratio of melamine to glucose, the concentration of nitrogen atom in the sample can be adjusted effectively: when the mass ratio of the two changes from 10 to 40, the amount of nitrogen atom doping gradually decreases from 21.26 at% to 18.79 ataspects. Compared with dicyandiamide, melamine has more advantages: when the mass ratio of both and glucose is the same, the nitrogen doping concentration in the sample is basically the same. However, the yield of melamine was higher than that of dicyandiamide. The effect of pyrolysis temperature on the concentration of nitrogen doping in the sample was studied when the mass ratio of melamine to glucose was 20:00. The results show that the nitrogen doping concentration can be controlled in a wide range by changing the pyrolysis temperature. When the pyrolysis temperature increases from 700 鈩，
本文编号：2187746
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