氧化铁复合材料的制备、表征与性能研究

发布时间：2018-02-11 10:49

本文关键词： 溶剂热吸附性能光催化性能电化学性能磁学性能　出处：《陕西科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：氧化铁是一种重要的磁性材料,在吸附、催化、锂离子电池、传感器和生物医药等方面具有广阔的应用前景。然而,随着研究的深入,发现单一氧化铁存在不同程度的缺陷,通过两种或两种以上纳、微米结构单元的有效组装可以实现氧化铁纳米材料的优异性能以及多元功能。因此,对氧化铁及其复合材料的探索具有重要的意义。本论文主要采用溶剂热法成功的制备了磁性多孔α-Fe2O3纳米片,磁性Fe3O4纳米材料和磁性石墨烯/Fe3O4纳米复合材料。通过多种分析方法对磁性纳米材料的结构进行了表征,并探讨了其吸附、光催化、磁性和电化学性能。其研究内容如下:1.采用简单的溶剂热法和高温煅烧法成功地制备出尺寸均一的多孔α-Fe2O3纳米片。所制备的α-Fe2O3纳米片通过各种分析手段进行了表征。结果显示:所制备的α-Fe2O3纳米片是六方相结构,并且表现出多孔片状结构。所制备的α-Fe2O3纳米片对一些染料(例如藏红T,吡罗红,亚甲基蓝,罗丹明B)进行了光催化实验,结果表明,在紫外光照射下,多孔α-Fe2O3纳米片可以不同程度的降解这些染料,尤其对罗丹明B的降解率达到100%。此外,多孔α-Fe2O3纳米片表现出铁磁性质。2.通过简单的溶剂热法成功地制备出Fe3O4纳米十二面体。所制备的Fe3O4纳米十二面体通过各种分析手段进行了表征。结果表明,PEG-10000通过吸附在特定面可以调节晶面的生长速率,并且进一步影响Fe3O4纳米十二面体的形成。此外,制备的Fe3O4纳米十二面体不仅可以有效的降解一些有机染料(例如藏红T和刚果红)而且还具有良好的磁响应,其在染料溶液中通过外加磁场在短时间实现快速分离。3.采用简单的溶剂热法成功地制备出尺寸均匀的Fe3O4纳米粒子。结构与尺寸分析表明:所制备的Fe3O4纳米粒子为立方相结构,平均粒径30nm,尺寸均一,分散性较好。将Fe3O4纳米粒子应用于有机染料(如亚甲基蓝、藏红T)光催化降解实验发现,所制备的Fe3O4纳米粒子具有优异的光催化降解性能,降解率较高,且3次重复实验光催化效果接近。此外,制备的Fe3O4纳米粒子在室温下还具有很强的饱和磁化强度,可以实现光催化剂与染料溶液的分离,避免二次污染。4.采用简单的一步溶剂热方法成功地制备出石墨烯/Fe3O4(GN/Fe3O4)复合材料。表征结果表明,平均尺寸为40nm的Fe3O4纳米粒子均匀的分散到石墨烯层上,其有效的避免了石墨烯的团聚。通过对某些有机染料(例如吡罗红、亚甲基蓝、甲基橙和罗丹明B)进行光催化降解实验,结果表明,制备的GN/Fe3O4复合材料在紫外光照射下呈现出优异的光催化降解活性,对这些染料的降解率都可以达到90%以上。并且制备的GN/Fe3O4复合材料对降解染料具有良好的稳定性,多次降解染料其降解率仅略微下降。此外,制备的GN/Fe3O4复合材料具有铁磁行为,在外加磁场的作用下可以有效的从染料溶液中分离出来,其在催化剂的循环使用及其减小催化剂的污染方面有潜在的应用。5.采用简单的一步溶剂热方法成功地制备出石墨烯/Fe3O4(GN/Fe3O4)纳米复合材料,氧化石墨烯还原成石墨烯的过程和Fe3O4纳米粒子的生成同时进行。所制备的复合纳米材料通过不同的分析技术进行了表征。结果表明,平均尺寸为30nm的Fe3O4纳米粒子密集和均匀的分散到石墨烯层上,其有效的避免了Fe3O4的团聚。所制备的GN/Fe3O4纳米复合材料作为锂离子电池的负极材料,在电流强度为100m Ag-1时,呈现出较高的充放电比容量,循环70圈后,放电比容量仍可以达到1165m Ahg-1,然而单一的Fe3O4纳米粒子,其降低到431m Ahg-1。GN/Fe3O4纳米复合材料比单一的Fe3O4纳米粒子表现出优异的倍率性能。此外,所制备的GN/Fe3O4复合材料具有铁磁行为,在外加磁场的作用下可以有效的从溶液中分离出来。
[Abstract]:Iron oxide is a kind of important magnetic materials in adsorption, catalysis, lithium ion battery, and has broad application prospects of sensors and biomedicine. However, with the deepening of the study, found that single iron oxide defects in different degrees, by two or more than two kinds of nano micron structure, effective assembly unit can achieve excellent the performance of iron oxide nano materials and multiple functions. Therefore, is of great significance to explore the iron oxide and its composite materials. This paper mainly uses the solvothermal method was successfully prepared with magnetic porous alpha -Fe2O3 nanosheets, Fe3O4 magnetic nanoparticles and magnetic graphene /Fe3O4 nanocomposites. Through a variety of methods on the structure analysis of magnetic nano materials were characterized and investigated the adsorption, photocatalysis, magnetic and electrochemical properties. The research contents are as follows: 1. using a simple solvothermal method and high temperature calcination Burning method successfully prepared porous alpha -Fe2O3 nanosheets with uniform size. The alpha -Fe2O3 nanosheets prepared by various analytical methods were investigated. The results show that the preparation of alpha -Fe2O3 nanosheets prepared is the six phase structure, and exhibits a porous lamellar structure. The preparation of nano -Fe2O3 alpha for some dyes (such as Safranine T, pyronine B, methylene blue, Luo Danming) the photocatalytic experiment, results showed that under UV irradiation, porous alpha -Fe2O3 nanosheets degraded the dye, especially on the degradation rate of 100%. in Luo Danming B, -Fe2O3 nano porous alpha film ferromagnetic properties of.2. by a simple solvothermal method successfully prepared nano Fe3O4 twelve surface. The prepared nano Fe3O4 twelve surface were characterized by various analytical methods. The results showed that PEG-10000 adsorbed on the surface can be regulated by specific crystal plane The growth rate, and further affect the formation of nanometer Fe3O4 twelve surface. In addition, the preparation of nano Fe3O4 twelve surface not only can effectively degrade some organic dyes (such as Safranine T and Congo red) but also has good magnetic response, the externally applied magnetic field in a short time to achieve rapid separation by simple.3. the solvothermal method successfully prepared Fe3O4 nanoparticles with uniform size in the dye solution. The structure and size analysis showed that the Fe3O4 nanoparticles are cubic phase structure, uniform size, average particle size of 30nm, good dispersion of Fe3O4 nanoparticles in organic dyes (such as methylene blue and safranin T) found that the photocatalytic degradation, Fe3O4 nanoparticles have excellent photocatalytic properties, the degradation rate is higher, and 3 repeated experiments close to the photocatalytic effect. In addition, the preparation of Fe3O4 nano particles at room temperature Also has a very strong saturation magnetization, can realize the separation of photocatalyst and dye solution, avoid pollution two.4. using a simple one-step solvothermal method successfully prepared graphene /Fe3O4 (GN/Fe3O4) composite material. The characterization results showed that the average size of Fe3O4 nanoparticles of 40nm uniformly dispersed into graphene layer on the effective avoid the graphene reunion. Based on some organic dyes (e.g. pyronine, methylene blue, methyl orange and Luo Danming B) photocatalytic degradation experiments, the results show that the prepared GN/Fe3O4 composite showed excellent photocatalytic activity under UV irradiation, the degradation of these dyes the rate can reach more than 90%. And the GN/Fe3O4 composite material prepared has good stability on the degradation of dyes, the degradation rate of dye degradation times only slightly decreased. In addition, the GN composite material prepared by /Fe3O4 The material has a ferromagnetic behavior under magnetic field can be effectively separated from the dye solution, the potential application of.5. using a simple one-step solvothermal method successfully prepared graphene /Fe3O4 in the catalyst circulation and reduce the pollution of catalyst (GN/Fe3O4) nano composite oxide graphene reduced to graphene and Fe3O4 nanoparticles simultaneously. The composite nano materials prepared by different analytical techniques were investigated. The results show that the average size of 30nm Fe3O4 nanoparticles densely and uniformly dispersed into the graphene layer, which can effectively avoid the agglomeration of Fe3O4 for GN/Fe3O4. Nano composite materials were used as anode materials for lithium ion batteries, the current intensity is 100m Ag-1, showing a higher discharge capacity, after 70 cycles, the discharge capacity still In order to achieve the 1165m Ahg-1, however, Fe3O4 nanoparticles, the rate performance of 431m Ahg-1.GN/Fe3O4 nanocomposites than single Fe3O4 nanoparticles show excellent. In addition, the GN/Fe3O4 composite material prepared with ferromagnetic behavior under magnetic field can be effectively separated from the solution.

【学位授予单位】：陕西科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332;TB383.1

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