基于电荷转移的分子磁性薄膜的设计与研究

发布时间：2018-03-19 17:51

本文选题：电荷转移　切入点：磁性薄膜　出处：《大连理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：现代电子信息技术朝着微型化、超高密度存储的方向在不断地发展,将分子磁性材料薄膜化或制成相应的微磁器件是满足这一发展的最有效途径。磁性薄膜由于其独特的特性,如结构稳定,较强的磁各向异性等,目前在磁存储、磁记忆、磁开关等方面已有许多应用。在这其中,电荷转移磁性复合薄膜可以利用外界刺激控制分子内白旋电子的迁移,调控自旋之间的耦合作用以及磁各向异性,从而实现分子层次上磁性双稳态的调控,这引起了世界各国研究者们的注意。因此我们设想,选用具有双稳态性质的磁性晶体材料为原料,具有较高玻璃化转变温度的高分子为载体,利用高分子与晶体间形成的氢键相互作用来制备一类既能保持原有晶体特性且可重复制备的高质量薄膜,这将是一个有趣但富有挑战性的工作。基于以上构想,本课题从以下两方面来开展工作：1、制备难溶性晶体Fe2Co的电荷转移磁性复合薄膜室温下,构筑基元[Fe(pzTp)(CN)3]与第二配体4-吡啶醛肟以及Co(ClO4)2·6H2O进行自组装合成了结构为异金属一维双之字链的Fe2Co磁性晶体材料。Fe2Co晶体具有双稳态,可以利用外界刺激实现其分子层次上磁性双稳态的调控,是制备电荷转移磁性复合薄膜的理想材料。由于Fe2Co晶体的一维链状结构,其本身难溶于有机溶剂DMF,所以制备薄膜过程中晶体颗粒的溶解需要借助于外界长时间的超声作用。制备的Fe2Co薄膜中针状的晶体颗粒仅是部分镶嵌于高分子HPMC中,薄膜表面的均匀性与致密性较差,但薄膜中原有晶体的主要结构并没有发生改变,并且所制备的薄膜结构性能稳定、可重复制备。2、制备可溶性晶体Fe2Co2的电荷转移磁性复合薄膜室温下,构筑基元[Fe(Tp)(CN)3]-与第二配体2,2'-二毗啶胺以及Co(NO)3·6H2O进行自组装合成具有分子四方结构的零维四核晶体材料Fe2Co2。以Fe2Co2这种易溶性的且具有双稳态性质的磁性晶体材料为原料,高分子HPMC为载体,利用高分子本身良好的分散性和优良的成膜能力,通过溶胶-凝胶的成膜方法和浸渍-涂布的涂膜方式,成功制备出了保持原有双稳态性质、结构稳定、均匀致密且可重复制备的Fe2Co2电荷转移磁性复合薄膜。电荷转移磁性复合薄膜的成功制备实现了分子磁性材料的功能化转变,同时也为磁性材料的应用拓展了一条新的途径,可以应用于传感器、磁开关等方面。
[Abstract]:Modern electronic information technology is developing in the direction of miniaturization and ultra-high density storage. Thinning molecular magnetic materials or making corresponding micromagnetic devices is the most effective way to meet this development. For example, stable structure, strong magnetic anisotropy and so on, there are many applications in magnetic storage, magnetic memory, magnetic switch and so on. Among them, the charge transfer magnetic composite film can control the transfer of intramolecular white spin electrons by external stimulation. The regulation of spin-to-spin coupling and magnetic anisotropy to achieve the regulation of magnetic bistability at the molecular level has attracted the attention of researchers all over the world. The bistable magnetic crystal material is used as raw material, and the polymer with high glass transition temperature is used as carrier. It will be an interesting but challenging work to prepare a class of high quality films which can retain the original crystal properties and can be prepared repeatedly by using the hydrogen bond interaction between the polymer and the crystal. In this paper, the following two aspects of work were carried out to prepare the charge transfer magnetic composite films of insoluble crystal Fe2Co at room temperature. Self-assembly of Fe(pzTp)(CN)3 with the second ligand 4-pyridyl aldoxime and Co(ClO4)2 路6H2O the bistable structure of the Fe2Co magnetic crystal material. Fe2Co crystal with one-dimensional double zigzag chain was synthesized. The control of magnetic bistability at molecular level can be realized by external stimulation, which is an ideal material for the preparation of charge transfer magnetic composite films. Because of the one-dimensional chain structure of Fe2Co crystal, It is insoluble in the organic solvent DMF, so the dissolution of the crystal particles in the preparation process of the film needs the help of the external long-term ultrasonic action. The needle-like crystal particles in the prepared Fe2Co thin film are only partially embedded in the high molecular HPMC. The surface uniformity and densification of the films are poor, but the main structure of the original crystals in the films has not changed, and the structure and properties of the films prepared are stable. The charge transfer magnetic composite films of soluble crystal Fe2Co2 can be prepared repeatedly at room temperature. Self-assembly synthesis of zero-dimensional tetranuclear crystal material Fe _ 2Co _ 2 with molecular tetragonal structure by self-assembly with the second ligand 2O2O2-dipyridamine and Co(NO)3 路6H2O was carried out using Fe2Co2, a readily soluble and bistable magnetic crystal material, as the raw material for the synthesis of Fe _ 2Co _ 2, a structuring unit [Fe(Tp)(CN)3], and its second ligand, dipyridamine, and Co(NO)3 路6H _ 2O. The polymer HPMC was successfully prepared by the sol-gel film forming method and the impregnation-coating method, using the excellent dispersity and excellent film forming ability of the polymer, and maintaining the original bistable property and the stable structure, by using the sol-gel method and the impregnation-coating method, the polymer HPMC was used as the carrier, and the structure of the polymer was stable. Uniform dense and repeatable Fe2Co2 charge transfer magnetic composite thin films. The successful preparation of charge transfer magnetic composite thin films has realized the functional transition of molecular magnetic materials, and has also opened a new way for the application of magnetic materials. It can be used in sensor, magnetic switch and so on.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.2

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