本文選題：碳納米復合材料　切入點：層狀氫氧化物　出處：《北京化工大學》2015年碩士論文

【摘要】：碳納米復合材料有機結合了碳和納米微粒兩者優(yōu)異的性能,因此在能量存儲與轉換、藥物運載、環(huán)境、催化等領域有廣泛的應用。目前碳納米復合材料通�；诩褐苽涞募{米碳材料(如石墨烯、碳納米管)液相合成,存在制備工藝復雜、成本高、均勻性差、納米微粒易團聚等缺點,因此,尋求一種簡單高效的方法制備尺寸均勻、分散性高的碳納米復合材料是亟需解決的重要課題。本論文以有機陰離子插層層狀氫氧化物為單一前驅體,經一步固態(tài)熱解可控合成及組裝得到一種新型高質量、多功能的六方片狀碳/金屬/金屬氧化物納米復合材料,并將其應用于污染物去除和催化劑載體領域。主要研究內容如下：1.以水楊酸根(sal)插層的層狀氫氧化物Co(Mg)Al-sal LDH為前驅體,無需還原劑和額外碳源一步固態(tài)熱解得到六方片狀C/Co/Mg(Al)O及C/Co/Al2O3納米復合材料,研究金屬元素比例、熱解溫度對復合材料組成和結構的影響。利用XRD、SEM、TEM、FT-IR、Raman、XPS、BET及VSM等表征手段對前驅體和碳納米復合材料進行了詳細表征。結果表明,得到的C/Co/Mg(Al)O納米復合材料保持前驅體的六方片狀結構,Co (8nm)和Mg(Al)O (3-5nm)納米粒子均勻分散在石墨化的碳基底中；碳表面存在大量的-OH和-COOM,證明碳納米復合材料表面功能化；具有較大的比表面積(600℃,207 m2/g)和豐富的孔結構；該碳納米復合材料具有較高的飽和磁化強度,表現出優(yōu)異的磁學性能。2.將C/Co/Mg(Al)O及C/CO/Al2O3內米復合材料應用于有機染料的去除,詳細研究了焙燒溫度、金屬元素比例、溶液pH值和溫度對吸附劑吸附效果的影響,并對其吸附機理進行探究。研究發(fā)現,該復合材料對陰離子染料剛果紅、橙黃Ⅱ、甲基橙、伊文思藍均表現出優(yōu)異的吸附性能,如對染料剛果紅,最大吸附量為2787mg/g,優(yōu)于文獻中報道的吸附材料；該納米復合材料能夠磁性回收并可多次重復利用。機理研究表明,該納米復合材料中的Mg(A1)O表現出較高的活性,在水溶液中發(fā)生LDHs結構復原,大大提高其與染料的吸附位點,而且該材料表面存在大量的功能基團和豐富的孔結構使得C/Co/Mg(Al)O納米復合材料對染料顯示出優(yōu)異的吸附性能。3.利用LDHs前驅體法一步固態(tài)熱解得到六方片狀C/Mg(Al)O納米復合材料,經酸溶蝕,無需模板及催化劑的條件下得到新型六方片狀石墨化多孔碳。對該碳材料進行一系列詳細表征,結果表明,得到的碳材料具有較大的比表面積(658 m2/g)、豐富的孔結構、高石墨化程度且表面含有大量的功能基團-OH不-coo-,是一類理想的催化劑載體材料。在其表面負載Ag,無需還原劑即可原位得到六方片狀C/Ag納米復合催化劑,其中,Ag納米微粒(8nm)均勻分散在多孔碳載體上。該催化劑在對硝基苯酚催化加氫反應中表現出較高的催化活性和穩(wěn)定性。
[Abstract]:Carbon nanocomposites have been widely used in energy storage and conversion, drug delivery, environment, catalysis and so on.At present, carbon nanocomposites are usually based on liquid phase synthesis of nano-carbon materials (such as graphene, carbon nanotubes), which have the disadvantages of complex preparation process, high cost, poor homogeneity and easy agglomeration of nanoparticles.It is an important task to find a simple and efficient method to prepare carbon nanocomposites with uniform size and high dispersion.In this paper, a new high quality, multifunctional hexagonal carbon / metal / metal oxide nanocomposite was synthesized and assembled by one-step solid pyrolysis with organic anion intercalated layered hydroxides as a single precursor.It is applied to the field of pollutant removal and catalyst support.The main research contents are as follows: 1.Using layered hydroxide Co(Mg)Al-sal LDH intercalated with salicylic acid as precursor, hexagonal C/Co/Mg(Al)O and C/Co/Al2O3 nanocomposites were prepared by one step solid pyrolysis without reducing agent and extra carbon source.Effect of pyrolysis temperature on composition and structure of composites.The precursor and carbon nanocomposites were characterized in detail by means of XRDD-SEMM-TEMT-IRT- Ramanhe XPS-BET and VSM.The results show that the prepared C/Co/Mg(Al)O nanocomposites keep the precursor hexagonal sheet structure (8nm) and Mg(Al)O (3-5nm) nanoparticles dispersed uniformly in graphitized carbon substrates, and there are a large number of -OH and -COOM on the carbon surface, which proves the functionalization of the carbon nanocomposites.It has a large specific surface area of 600 鈩，

本文編號：1705855