经Fe(NO_3)_3处理的γ-Fe_2O_3/Ni_2O_3复合纳米微粒分析  

Analysis of γ-Fe_2O_3/Ni_2O_3 Composite Nanoparticles after Fe(NO_3)_3 Treatment

作　　者：林立华[1] 周群[1] 卜胜利[2] 

机构地区：[1]上海理工大学大学物理实验中心,上海200093 [2]上海理工大学理学院,上海200093

出　　处：《表面技术》2015年第9期72-77,共6页Surface Technology

基　　金：上海高校青年教师培养资助计划(ZZSLG14029)~~

摘　　要：目的研究经Fe(NO3)3处理后γ-Fe2O3/Ni2O3复合纳米微粒稳定分散在磁性液体中的机理。方法使用共沉淀法制备Fe OOH/Ni(OH)2前躯体,经Fe Cl2溶液处理后得到以γ-Fe2O3为核心,Ni2O3在外层,Fe Cl3·6H2O在最外层的核-壳结构γ-Fe2O3/Ni2O3复合纳米微粒。用硝酸铁溶液对其进一步处理,使微粒表面性质稳定以适合配制离子型磁性液体。使用振动样品磁强计、透射电子显微镜、X射线衍射仪、X射线光电子能谱仪对硝酸铁处理后复合纳米微粒的磁性、形态、晶体结构、化学组成及结构进行分析。结果经硝酸铁处理后,微粒的磁性减弱,粒径略微变大,约为11 nm,但位于微粒核心的主要成分γ-Fe2O3保持不变,且在微粒表面包裹了一层Fe(NO3)3·9H2O抗腐蚀层。结论经Fe(NO3)3处理后微粒表面包裹的抗腐蚀层及配制磁性液体时微粒表面吸附同种H+或OH-形成的静电斥力,使微粒在磁性液体中稳定分散。Objective To investigate the mechanism of γ-Fe2O3/ Ni2O3 composite nanoparticle stably dispersed in the ferrofluids after Fe（ NO3）3treatment. Methods The Fe OOH / Ni（ OH）2precursor was prepared by coprecipitation,and was then treated with the Fe Cl2 solution to obtain composite nanoparticles containing γ-Fe2O3 core,Ni2O3external shell and Fe Cl3·6H2O outermost layer. The nanoparticles were then treated with Fe（ NO3）3to obtain modified particles with stable surface properties for the preparation of ionic ferrofluids. The magneticity,morphology,crystal structure,chemical composition and structure of the composite nanoparticles after Fe（ NO3）3treatment were analyzed by VSM,TEM,XRD,EDX and XPS. Results The particles after treatment were slightly larger（ about 11 nm）,but the major component γ-Fe2O3 located in the core of particles remained unchanged. And the surface of the particles was covered with a Fe（ NO3）3·9H2O corrosion-resistant layer. Conclusion The corrosion-resistant layer covering the particles after Fe（ NO3）3treatment and the electrostatic repulsion formed by the same species H＋or OH-adsorbed onto the surface of the particles during the preparation of magnetic liquid made the particles stably dispersed in the ferrofluids.

关 键 词：复合纳米微粒 核-壳结构 Fe(NO3)3处理 磁化强度 抗腐蚀层 

分 类 号：TB383[一般工业技术—材料科学与工程]