溶剂热法制备纳米铁氧体的性能研究

发布时间：2018-06-16 20:39

本文选题：溶剂热法 + 锰锌铁氧体　；参考：《沈阳理工大学》2017年硕士论文

【摘要】：铁氧体因具有优越的理化机能,已被科学工作者普遍应用于通信、电子、医学以及生物工程等一系列领域。铁氧体自身具有生物相容性,且无害无毒无污染等优点,有望被用于生物医疗和肿瘤靶向治疗中,在生物和医学领域方面有着光明的未来。铁氧体的性能与纳米颗粒的形貌、粒径和分散性等息息相关相关,因而制备形貌可控、尺寸均一、性能稳定的纳米铁氧体具有特殊的意义。本文采用溶剂热合成了单分散的纳米锰锌铁氧体、镍锌铁氧体和钴锌铁氧体,并研究了不同反应条件对纳米铁氧体分散性、粒径、形貌和性能的影响,具体研究内容如下:(1)利用乙二醇为溶剂,聚乙二醇作为分散剂,氯化锌以及氯化铁等试剂作为反应体系中的前驱体,通过溶剂热法成功制备了铁氧体。分析了表面活性剂含量、分散剂的加入量以及溶液温度变化等一系列因素对产物的形貌、团聚性和分散度的影响。并通过扫描电子显微镜、振动样品磁强计、傅立叶变换红外光谱射仪、X衍射仪以及交变磁场发生器等对产物物相、形貌、磁热和磁性能分析和研究。通过研究获得最佳工艺条件为:加入0.8mmol的聚乙二醇、5mmol氯化铁、反应温度为180℃、20mmol的乙酸铵。在最佳工艺条件下,得到的纳米锌铁氧体是单分散的,结晶性和性能良好。并且在5-25℃条件下表现出亚铁磁性。(2)在最优工艺条件下,合成了MnxZn1-xFe2O4铁氧体(x=0.2,0.4,0.6,0.8)并通过扫描电子显微镜、振动样品磁强计、X衍射仪、傅立叶变换红外光谱射仪和磁热性能等手段对样品进行了表征。XRD分析结果表明,制备的锰锌铁氧体是立方尖晶石结构、产物纯度高、结晶性能好、随着x值的不断增加,镍锌铁氧体晶格常数逐渐减小。磁性能分析结果表明,锰锌铁氧体在5-25℃条件下呈现出亚铁磁性,因而可以通过改变锰和锌的值,来改变产物的磁性能和磁热性能。(3)制备了单分散的纳米NixZn1-xFe2O4铁氧体(x=0.2,0.4,0.6,0.8),研究了不同摩尔比,对产物的磁性能和磁热性能的影响。通过研究发现,产物在5-25℃条件下均表现出亚铁磁性。随着x值不断上升,样品的饱和磁化强度出现变化先上升后不断下降特点。在x=0.2时,达到最大值且具有较大的磁滞回线面积。样品磁热性能和磁性能出现相似的变化趋势,Ni0.6Zn0.4Fe2O4纳米铁氧体显现出优异的磁性能和磁热性能等优点,在50kHz交变磁场中响应600s,最终温度达到63.6℃。(4)制备了纳米钴锌铁氧体CoxZn1-xFe2O4(x=0.1,0.3,0.5,0.7),SEM结果表明,产物的分散性较好,尺寸均一。从物相分析结果显示获得产物具有高纯度的立方尖晶石结构。且制备铁氧体晶格常数,随x值上升而逐渐减小。x=0.1、0.3、0.5和0.7时,对应的晶格常数分别为0.8434nm、0.8426nm、0.8418nm、0.8410nm。产物在5-25℃条件下都显现良好的亚铁磁性,当钴含量的上升时,钴锌铁氧体磁性能逐渐上升。在外加磁场条件下,产物磁热效应十分显著,Co0.3Zn0.7Fe2O4在50kHz交变磁场中持续响应600s,最终温度能达到101.8℃。
[Abstract]:Ferrites have been widely used in a series of fields, such as communication, electronics, medicine and Bioengineering, because of their superior physical and chemical functions. Ferrites have the advantages of biocompatibility, harmless and non-toxic and non polluting. They are expected to be used in biological medical and tumor targeting treatment, and have a bright future in the field of biology and medicine. In the future, the properties of ferrite are closely related to the morphology, particle size and dispersion of nanoparticles. Therefore, the preparation of nano ferrite with controllable morphology, uniform size and stable performance is of special significance. In this paper, the monodisperse nano manganese zinc ferrite, nickel zinc ferrite and cobalt zinc ferrite are synthesized by solvent heat. The effects of reaction conditions on the dispersion, particle size, morphology and properties of nano ferrite were studied. The contents of the study are as follows: (1) using glycol as the solvent, polyethylene glycol as a dispersant, zinc chloride and ferric chloride as precursors in the reaction system, the ferrite was successfully prepared by solvent thermal method. The content of the surfactant was analyzed. The effects of a series of factors such as the amount of dispersant and the temperature change of the solution on the morphology, aggregation and dispersion of the products, and the analysis and study of the phase, morphology, magnetic heat and magnetic properties of the products by scanning electron microscope, vibrating sample magnetometer, Fu Liye transform infrared spectrometer, X diffractometer and alternating magnetic field generator. The optimum technological conditions are as follows: 0.8mmol's polyethylene glycol, 5mmol ferric chloride, the reaction temperature of 180 C, 20mmol ammonium acetate. Under the optimum conditions, the nano zinc ferrite is monodisperse, crystallinity and properties are good. And the ferromagnetism is shown at 5-25 C. (2) under the optimal process conditions, the synthesis is made. MnxZn1-xFe2O4 ferrite (x=0.2,0.4,0.6,0.8) was characterized by scanning electron microscope, vibrating sample magnetometer, X diffractometer, Fu Liye transform infrared spectroscopy and magnetic properties. The results of.XRD analysis showed that the prepared manganese zinc ferrite was a cubic spinel structure with high purity and good crystallization performance with X. The lattice constant of Ni Zn ferrite decreases gradually. The magnetic energy analysis results show that the manganese zinc ferrite exhibits ferromagnetism at 5-25 C, so the magnetic and magneto-thermal properties of the products can be changed by changing the value of manganese and zinc. (3) the monodisperse nano NixZn1-xFe2O4 ferrite (x=0.2,0.4,0.6,0.8) is prepared. The effects of different molar ratios on the magnetic properties and magnetic properties of the products have been studied. It is found that the products exhibit ferromagnetic properties at 5-25 C. As the x value increases, the saturation magnetization of the samples rises first and then decreases. At the time of x=0.2, the maximum value is reached and the hysteresis area is larger. The magneto-thermal properties and magnetic properties of the samples have a similar trend. The Ni0.6Zn0.4Fe2O4 nano ferrite exhibits excellent magnetic and magneto-thermal properties. The response to 600s in the 50kHz alternating magnetic field is 63.6. (4) the nano cobalt zinc ferrite CoxZn1-xFe2O4 (x=0.1,0.3,0.5,0.7) is prepared, and the SEM results show the dispersion of the products. The result of phase analysis shows that the obtained product has high purity cubic spinel structure. And the lattice constant of ferrite is prepared. With the increase of x value, the corresponding lattice constants are 0.8434nm, 0.8426nm, 0.8418nm, and 0.8410nm. products are all good under the condition of 5-25. Ferromagnetism, when the cobalt content rises, the magnetic properties of cobalt zinc ferrite gradually rise. Under the applied magnetic field, the magneto thermal effect of the product is very significant. The Co0.3Zn0.7Fe2O4 in the 50kHz alternating magnetic field continues to respond to 600s, and the final temperature can reach 101.8 degrees C.
【学位授予单位】：沈阳理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM277;TB383.1

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