铁氧体纳米粉体的制备与表征研究
作者：段红珍
院校:华北工学院
关键字:
学位：硕士
专业:应用化学
摘要:
本文介绍了铁氧体纳米粉体的发展历史和典型的制备方法，重点研究了在溶胶凝胶法制备钴铁氧体(CoFe2O4)、钡铁氧体(BaFe12O19)纳米粉体的过程中工艺条件对粒径及其均匀性等物理性能的影响，在此基础上制备了尖晶石型纳米级钴铁氧体、M型钡铁氧体及其掺镧（La）体系，并对它们进行了充分的表征。 （一）、通过溶胶凝胶法与共沉淀法的对比，确证了溶胶凝胶法用于制备纳米铁氧体的优势与可行性。通过对初始组分及反应条件的研究，采用柠檬酸溶胶凝胶技术成功地制备了纳米钴铁氧体与钡铁氧体；详细研究了起始溶液pH值、柠檬酸配比、表面活性剂、煅烧条件等对铁氧体纳米粉体性能参数的影响，利用透射电子显微镜（TEM）、X-射线衍射技术(XRD) 对粉体粒径和结构进行测试，并结合其它测试手段，探索了最佳制备条件。 （二）、在最佳制备条件下，成功地制备了钴铁氧体与钡铁氧体的掺镧体系，利用TEM和XRD对其粒径与结构进行表征，通过能谱仪对其进行成分分析，并采用振荡样品磁强计(VSM)对铁氧体与掺镧铁氧体纳米粉体进行磁性研究。 本研究首次制得未见文献报道的均匀棒状钡铁氧体及掺镧钡铁氧体纳米粉体，并研究确定了其最佳的制备工艺条件。 研究过程中，还采用扫描电子显微镜（SEM），热分析法（DSC），红外光谱（FTIR），X射线能谱（EDS）等多种测试手段和方法对所制样品进行了充分的表征与性能测试。
Abstract:
In this paper, the developed history and representative methods of nanostructured ferrite were introduced, and Cobalt ferrite (CoFe2O4), Barium ferrite (BaFe12O19) and their La dopping system mostly was studied by Sol-Gel. The processing conditions which affect ferrite particles size and homogeneous degree etc physical properties were reasearched, then the spinel Cobalt ferrite, M-type Barium ferrite and their La dopping system were prepared and Characterized in this investigation. The advantages and feasibility of Sol-Gel method were confirmed by comparing and contrasting Sol-Gel method with coprecipitation method. By investigating initial component and condition, Cobalt ferrite and Barium ferrite were synthesized by citrate Sol-Gel method. The pH value of initial solution, the molar ratio of nitra/citric, active agent, heat treat temperature and time etc were investigated to clarify the forming conditions of the ferrites. The particles size, morphology were studied by means of transmission electron microscopy (TEM) and X-ray diffraction (XRD), and other measurements were used to characterize samples, Then the perfect synthesized conditions of the ferrites were find out in this investigation. The doped Cobalt ferrite and Barium ferrite were synthesized in the condition of the perfect synthesized conditions. The particles size, morphology were characterized by TEM and XRD. The magnetic property was measured with vibrating sample magnetometer (VSM). The homogeneous rod-like BaFe12O19 and doped La Barium ferrite nano-particles were prepared under proper conditions for the first time. The rod-like Barium ferrite was not seen in reported literatures. The synthesized samples were adequately measured using multi-methods. The other Measure instruments include, scanning electron microscopy（SEM），thermal analysis system（DSC），fourier infrared spectrum（FTIR），X-ray energy spectrum（EDS）etc.