【摘要】：石墨烯是一種二維結構的碳原子薄膜,因為它出色的性質和潛在的應用價值正在吸引著越來越多的科學關注。氮元素摻雜是一種有效改善石墨烯能帶結構和性質的方法,對于拓展石墨烯的應用非常重要。本論文利用高溫熱解法成功制備氮摻雜石墨烯并對其進行了詳細表征。主要內容如下:1、采用高溫熱解雙氰胺和葡萄糖混合物的方法成功制備了高氮含量的摻雜石墨烯。測試結果顯示,通過改變雙氰胺和葡萄糖質量比可以實現(xiàn)對樣品中氮原子摻雜濃度的有效調節(jié):當兩者質量比從5~20變化時,氮原子摻雜量從22.44 at%逐漸減少到17.77 at%。氮原子在石墨烯中共有三種形式,分別是吡啶型氮、吡咯型氮和石墨型氮。熒光測試結果表明,石墨型氮是導致樣品熒光猝滅現(xiàn)象的主要原因,熒光猝滅率隨著石墨型氮濃度的增大而增大。2、采用高溫熱解三聚氰胺和葡萄糖混合物的方法成功制備了高氮含量的摻雜石墨烯。測試結果顯示,三聚氰胺和雙氰胺一樣,可以在氮摻雜石墨烯的形成過程中起到模板劑和氮源作用。通過改變三聚氰胺和葡萄糖質量比可以實現(xiàn)對樣品中氮原子摻雜濃度的有效調節(jié):當兩者質量比從10~40變化時,氮原子摻雜量從21.26 at%逐漸減少到18.79 at%。和雙氰胺相比,使用三聚氰胺更有優(yōu)勢:在兩者和葡萄糖質量比相同的情況下,樣品中氮摻雜濃度基本一致,但是使用三聚氰胺比使用雙氰胺能夠獲得更高的產率。3、在三聚氰胺和葡萄糖質量比為20時,研究了熱解溫度對樣品中氮摻雜濃度的影響。測試結果顯示,通過改變熱解溫度可以實現(xiàn)對樣品中的氮摻雜濃度的大范圍調控,當熱解溫度從700℃升高到900℃度變化時,樣品中氮摻雜濃度從33.32 at%逐漸減少到10.87 at%。三種氮原子熱穩(wěn)定性不同:吡啶型氮和吡咯型氮的熱穩(wěn)定性較差,濃度隨著溫度的升高而降低;石墨型氮的熱穩(wěn)定性較好,濃度在700℃到900℃范圍內基本是保持不變。本論文研究結果顯示,高溫熱解法是一種能夠有效制備氮摻雜石墨烯方法,這將有利于促進石墨烯的進一步應用。
[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，

本文編號：2187746