摘要
以硝酸铁和正硅酸乙酯分别作为氧化铁和SiO2的前驱体,通过溶胶-凝胶工艺制备了γ-Fe2O3/SiO2纳米复合粉体.若使用氯化铁为氧化铁前驱体,SiO2基体中则会生成α-Fe2O3. 当干凝胶热处理温度较低时(T<400℃),复合粉体(硝酸铁为前驱体)以非晶态存在。当T达到600℃时,γ-Fe2O3粒子在SiO2基体中大量形成.随着热处理温度的进一步升高,粉体中开始有α-Fe2O3杂质生成.使用盐酸做添加剂对复合粉体中γ-Fe2O3粒子大小及颗粒尺寸分布均有显著影响.
Nanocomposites with γ-Fe2O3 nanoparticles uniformly dispersed in silica matrix were successfully synthesized by using tetraethylorthosilicate (TEOS) as silica precursor and iron nitrate as ferric oxide precursor. However, when iron chloride was used as precursor, hematite was obtained in the final composite. It was found that the dried gels obtained at low temperatures (T 2O3 nanoparticles were formed, while a further increase of temperature resulted in γ to α-Fe2O3 transformation. The addition of acids to the sols resulted in a way to increase particle size and to narrow the particle size distribution of α-Fe2O3 in the composite.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第3期685-691,共7页
Journal of Inorganic Materials
关键词
γ-Fe2O3/SiO2
纳米复合粉体
溶胶-凝胶工艺
Iron oxides
Magnetic materials
Magnetic properties
Particle size analysis
Phase transitions
Silica
Sol
gels
Synthesis (chemical)
Transmission electron microscopy
X ray diffraction analysis
