【摘要】：石墨烯是一種新型納米材料,它獨(dú)特的結(jié)構(gòu)使其具有卓越的電學(xué)性能和物理性能,廣泛應(yīng)用在納米電子學(xué)、電子傳感器、晶體管、太陽能電池、催化劑等多種領(lǐng)域。但石墨烯沒有帶隙、較為惰性、不易與其他材料復(fù)合。向石墨烯中引入氮原子,形成氮摻雜石墨烯,可以改變其電子結(jié)構(gòu),并打開石墨烯的帶隙,從而使其具有更廣泛的應(yīng)用價(jià)值。本文采用水熱法合成氮摻雜石墨烯,分別以氨水和甲酰胺為氮源與氧化石墨烯反應(yīng),生成氮摻雜石墨烯。通過調(diào)控反應(yīng)條件,得到制備氮摻雜石墨烯的最適條件,即:以氨水為氮源,氧化石墨烯與氨水的質(zhì)量比為1:24、反應(yīng)溫度為160℃、反應(yīng)時(shí)間為12 h時(shí),產(chǎn)品中氮原子數(shù)百分比為9.08%,氮元素主要以吡啶氮的形式摻雜到石墨骨架當(dāng)中;以甲酰胺為氮源,氧化石墨與甲酰胺的質(zhì)量比為1:100、反應(yīng)溫度為140℃、反應(yīng)時(shí)間為12 h時(shí),產(chǎn)品中氮原子數(shù)百分比為5.67%,氮元素主要以吡咯氮的形式摻雜到石墨骨架當(dāng)中。以尿素為氮源,按照文獻(xiàn)42的方法制得了氮摻雜石墨烯,并對(duì)其進(jìn)行了表征。結(jié)合氨水、甲酰胺、尿素這三種氮源的實(shí)驗(yàn)結(jié)果,對(duì)石墨烯氮摻雜機(jī)理進(jìn)行了推斷。氮摻雜石墨烯具有一定的催化性,為了在反應(yīng)結(jié)束后便于將其從反應(yīng)體系中分離出來,可向氮摻雜石墨烯中引入磁性四氧化三鐵,將其制成磁性復(fù)合材料。本文利用水熱法,以氧化石墨烯和尿素鐵為原料、氨水為氮源、乙二醇和氨水為還原劑、聚乙烯吡咯烷酮(PVP)為分散劑,在反應(yīng)溫度為200℃條件下反應(yīng)12 h,一步反應(yīng)生成氮摻雜石墨烯-四氧化三鐵復(fù)合材料。利用紅外光譜,X射線衍射光譜、X射線光電子能譜、掃描電鏡、透射電鏡等手段對(duì)制備的復(fù)合材料進(jìn)行表征,結(jié)果表明,四氧化三鐵嵌入在氮摻雜石墨烯中,粒徑大多小于200 nm;X射線光電子能譜顯示,碳的原子百分比為70.34%,氮的原子百分比為5.43%,氧的原子百分比為21.23%,鐵的原子百分比為3%,氮元素主要以吡啶型為主。用氮摻雜石墨烯-四氧化三鐵復(fù)合材料作為甲苯氧化反應(yīng)的催化劑,雙氧水為氧化劑,并從反應(yīng)溫度、反應(yīng)時(shí)間、溶劑的種類、雙氧水加入量、催化劑用量、催化劑種類這六個(gè)方面,來考察影響甲苯催化氧化的因素。其中,反應(yīng)溫度60℃、反應(yīng)時(shí)間12 h、采用冰醋酸為溶劑、甲苯與雙氧水比例為1:4、催化劑0.2 g、催化劑吡啶氮含量最高時(shí),所得的甲苯氧化物苯甲醛的收率最高。
[Abstract]:Graphene is a new kind of nano-material, which has excellent electrical and physical properties due to its unique structure. It is widely used in nanoelectronics, electronic sensors, transistors, solar cells, catalysts and other fields. However, graphene has no band gap, is inert, and is not easy to be combined with other materials. The introduction of nitrogen atoms into graphene to form nitrogen-doped graphene can change its electronic structure and open the band gap of graphene so that it has more extensive application value. In this paper, nitrogen-doped graphene was synthesized by hydrothermal method. Nitrogen doped graphene was synthesized by the reaction of ammonia and formamide with graphene oxide. The optimum conditions for preparing nitrogen-doped graphene were obtained by adjusting the reaction conditions, namely, when ammonia was used as nitrogen source, the mass ratio of graphene oxide to ammonia water was 1: 24, the reaction temperature was 160 鈩，

本文編號(hào)：2288914