三唑亚铁纳米复合材料的制备及性能研究

发布时间：2018-09-01 07:17

【摘要】：自旋转换配合物作为分子磁性材料的前沿领域,由于其可控的双稳态性质在传感器、显示材料、信息存储及分子开关等方面有潜在的应用,从而受到了科学家们的广泛关注。三唑亚铁配合物是具有自旋转换特性的磁性材料,虽然能够在纳米级别保持良好的磁性协同性,但三唑亚铁纳米材料的易脆性和难加工性限制了其在实际功能性器件中的应用,而具有多功能的自旋转换纳米材料也成为科技发展的需求。因此,设计、合成不同的新型自旋转换纳米复合材料具有很重要的理论和现实意义。本课题旨在从基底复合、金纳米修饰和多步阶梯自旋转换行为三个方面设计、合成不同的三唑亚铁纳米复合材料,研究复合材料间的相互影响,尤其是三唑亚铁纳米材料自旋转换性能的变化情况:1.为了研究不同基底对三唑亚铁纳米材料的形貌和自旋转换性能的影响,我们分别以石墨烯、氧化铝膜(AAO)、阳离子交换树脂为基底,通过不同方法与三唑亚铁化合物复合成功得到了相应的自旋转换纳米复合材料:i)利用微乳液方法合成的[Fe(Htrz)2(trz)](BF4)纳米颗粒与石墨烯在乙醇溶液中以不同的质量比反应,获得了以石墨烯为基底的SCO-G纳米复合材料,电镜显示[Fe(Htrz)2(trz)](BF4)纳米颗粒(ca.50 nm)较均匀地分布在石墨烯表面,磁性结果表明纳米复合材料中[Fe(Htrz)2(trz)](BF4)纳米颗粒的自旋转换温度向高温区移动;ii)通过在不同的前驱体反应溶液中浸泡AAO膜,研究了[Fe(Htrz)2(trz)](Cl O4)和[Fe(NH2-trz)2(NH-trz)](Cl O4)纳米材料在AAO膜表面及孔道的生长情况,结果表明AAO膜的空间限制作用极大的影响了三唑亚铁纳米材料的形貌,并在磁性测试中得到了非常有意义的两步阶梯自旋转换现象;iii)同样采用在前驱体反应溶液中浸泡树脂球的方法,成功制备了以树脂球为基底的[Fe(Htrz)2(trz)](BF4)纳米棒阵列复合材料,SEM直观地表现了[Fe(Htrz)2(trz)](BF4)纳米棒在树脂表面不同时间段的生长情况,磁性测试证明自旋转换行为完好的保存在此特殊形貌的球状纳米棒阵列中。2.为了研究金纳米颗粒的光致热效应对三唑亚铁纳米材料光致自旋转换性能的影响,我们对两种不同尺寸的[Fe(Htrz)2(trz)](BF4)@Si O2纳米颗粒进行表面氨基功能化修饰,在其表面成功包覆了小粒径金纳米颗粒,由此得到了兼具有自旋转换性能和光致热效应的双功能纳米复合材料。拉曼光谱证明金纳米的光致热效应使得[Fe(Htrz)2(trz)](BF4)@Si O2@Au纳米颗粒在光致自旋转换过程中的能量需求降低了~100倍,同时由于金纳米良好的导热性,[Fe(Htrz)2(trz)](BF4)@Si O2@Au纳米颗粒在热致自旋转换过程中的的转变温度向高温移动,而热滞回线宽度有所减小。3.基于自旋转换纳米复合材料体系中由不同有机配体引起的多步阶梯自旋转换行为的研究空白,我们利用简便的连续微乳液法合成了具有核壳结构的[Fe(Htrz)2(trz)](BF4)@[Fe(NH2-trz)2(NH-trz)](BF4)纳米复合材料,利用SEM监控了它和[Fe(Htrz)2(trz)](BF4)、[Fe(NH2-trz)2(NH-trz)](BF4)在微乳液中不同时间段的生长情况,在磁性测试中也得到了预期的阶梯自旋转换行为。
[Abstract]:As the frontier of molecular magnetic materials, spin-exchange complexes have attracted much attention due to their controllable bistability, potential applications in sensors, display materials, information storage and molecular switches. Nano-scale magnetic synergy is maintained, but the brittleness and machinability of ferrous triazole nano-materials limit their applications in functional devices, and multi-functional self-rotating nano-materials have become the demand of the development of science and technology. The purpose of this project is to design and synthesize different triazole ferrous nanocomposites from three aspects: substrate composite, gold nano-modification and multi-step spin-exchange behavior, and to study the interaction between the composite materials, especially the change of the spin-exchange properties of triazole ferrous nanomaterials: 1. The influence of the substrate on the morphology and spin conversion properties of three azole iron nanomaterials, we have obtained the corresponding spin conversion nanocomposites by graphene, alumina membrane (AAO) and cation exchange resin based on different methods with three azole iron compounds: I) [Fe (Htrz) 2 (Trz) synthesized by microemulsion (BF4). SCO-G nanocomposites based on graphene were prepared by the reaction of graphene with nanoparticles in ethanol solution at different mass ratios. Electron microscopy showed that [Fe (Htrz) 2 (trz)] (BF4) nanoparticles (ca.50 nm) were uniformly distributed on the surface of graphene. Magnetic results showed that [Fe (Htrz) 2 (trz)] (BF4) nanoparticles were self-contained in the nanocomposites. (ii) The growth of [Fe (Htrz) 2 (trz)] (ClO 4) and [Fe (NH2-trz) 2 (NH-trz)] (ClO 4) nanomaterials on the surface of AAO films and the growth of pore channels were studied by immersing AAO films in different precursor reaction solutions. The results showed that the spatial confinement of AAO films greatly affected the morphology of triazole ferrous nanomaterials. Significant two-step spin-exchange phenomena were obtained in magnetic measurements; iii) The composite of [Fe (Htrz) 2 (trz)] (BF4) nanorod arrays was successfully prepared by immersing the resin balls in the precursor reaction solution, and the [Fe (Htrz) 2 (trz)] (BF4) nanorods were visually displayed on the resin surface by SEM. In order to study the effect of photothermal effect of gold nanoparticles on the photoinduced spin-exchange properties of ferrous triazole nanomaterials, we investigated the effects of two different sizes of [Fe (Htrz) 2 (trz)] (BF4) @Si O2 nanoparticles on the photoinduced spin-exchange properties of these nanorod arrays. The nanoparticles were successfully coated with small size gold nanoparticles by amino functional modification on the surface of the nanoparticles. The bifunctional nanocomposites with both spin-exchange properties and photothermal effects were obtained. Raman spectroscopy showed that the photothermal effect of the gold nanoparticles led to the photoinduced spin of [Fe(Htrz)2(trz)](BF4)@Si O2@Au nanoparticles. The energy requirement during the conversion process is reduced by ~100 times, and the transition temperature of [Fe(Htrz)2(trz)](BF4)@Si O2@Au nanoparticles in the thermo-induced spin-transfer process shifts to high temperature due to the good thermal conductivity of the gold nanoparticles, while the thermal hysteresis loop width decreases. In the research gap of multi-step spin conversion behavior, we have used a simple continuous microemulsion method to synthesize [Fe (Htrz) 2 (Trz)] (BF4) @[Fe (NH2-trz) 2 (NH-trz)] (BF4) nanocomposite with core-shell structure, and monitored it and [Fe (Htrz) 2 (SEM)) by using SEM, and the growth of ((2)) (NH2-trz) in the microemulsion at different time intervals. In the magnetic test, the expected step spin conversion behavior is also obtained.
【学位授予单位】：江南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;TB33

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