化学诱导相变法制备γ-Fe2O3磁性纳米微粒的尺寸研究
A Study of the Size of γ-Fe2 O3 Magnetic Nanoparticles Prepared by Chemically Induced Transition
-
摘要: 分别采用FeCl2溶液和FeCl2/NaO H溶液作为处理液,通过化学诱导相变法制备了γ‐Fe2 O3磁性纳米微粒。利用透射电子显微镜(TEM)、振动样品磁强计(VSM)、高分辨电子显微镜(HRTEM)和X射线衍射仪(XRD)对所制备纳米微粒的形貌、磁化性质、晶体结构进行表征与分析。结果表明,所制备的γ‐Fe2 O 3纳米微粒基本为球形微粒;由T EM确定的物理粒径大于由VSM测量确定的磁性粒径和由XRD确定的晶体粒径;且经添加的 NaO H处理制备的γ‐Fe2 O3磁性纳米微粒的粒径增大,磁性增强。实验结果还表明,具有对数正态分布尺寸的纳米晶体系,由Scherrer公式计算得到的晶体粒径对应体系的中值粒径而不是平均粒径。Abstract: γ‐Fe2 O3 magnetic nanoparticles were prepared by the method of chemically induced phase transi‐tion ,using FeCl2 solution or FeCl2/NaO H solution as the treating solution .T he morphology ,magnetiza‐tion properties and crystal structure of the nanoparticles were characterized and analyzed with transmission electron microscopy (TEM ) ,vibrating sample magnetometry (VSM ) ,high resolution electron microscopy (HRTEM) and X‐ray diffraction (XRD) .The experimental results showed that the γ‐Fe2 O3 nanoparticles were nearly spherical in shape ,their physical size determined by TEM was larger than their magnetic size determined by VSM or their crystal size determined by XRD ,and NaO H addition during their preparation resulted in a diameter increase and magnetic enhancement .Also ,for the nanocrystallite system having a log‐normal distribution diameter ,the grain size calculated using the Schereer formula corresponded to the median size rather than to the average size .
-
-
计量
- 文章访问数: 605
- HTML全文浏览数: 339
- PDF下载数: 52
- 施引文献: 0