%0 Journal Article
%T Preparation of Core-shell SiO2/Fe3O4 Nanocomposite Particles via Sol-gel Approach<br>溶胶-凝胶法制备核壳SiO2/Fe3O4复合纳米粒子的研究
%A LIU Bing
%A WANG De-Ping
%A HUANG Wen-Hai
%A YAO Ai-Hua
%A Ioku Koji
%A <br>刘冰
%A 王德平
%A 黄文hai
%A 姚爱华
%A 井奥洪二
%J 无机材料学报
%D 2008
%I Science Press
%X Core-shell structural SiO2/Fe3O4 nanocomposite particles with adjustable magnetic properties were prepared via a sol-gel process, in which the hydrolysis and condensation of TEOS were conducted on the surface of Fe3O4 nanoparticles under the aid of basic catalyst. The effects of the volume ratio of alcohol to water, the concentrations of ammonium and TEOS on the appearances and properties of the nanocomposite particles were investigated. The mechanism of the formation of SiO2/Fe3O4 nanocomposite particles was analyzed. Results show that silica shell is mainly formed from the aggregative growth of silica primary particles on the surface of Fe3O4 nanoparticles. With increasing the concentration of TEOS in the range of 0--0.02mol/L, the silica shell thickness increases on the condition of 0.3mol/L of NH4OH and 4:1 ratio of alcohol to water. Although the saturation magnetization of the nanocomposite particles decreases with the thickness of silica shell increasing, the coercive force of the particles is almost unchanged. And more, the nanocomposite particles remain favorable superparamagnetism.
%K sol-gel
%K core-shell structure
%K magnetite
%K silica<br>溶胶-凝胶
%K 核壳结构
%K 四氧化三铁
%K 二氧化硅
%K 溶胶
%K 凝胶
%K 法制
%K 核壳结构
%K 纳米粒子
%K 研究
%K Preparation
%K Approach
%K 超顺磁性
%K 矫顽力
%K 磁化强度
%K 复合粒子
%K 增厚
%K 壳层
%K 浓度低
%K 聚集生长
%K 表面
%K 初级粒子
%K 结果
%K 生成机理
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=84529CA2B2E519AC&jid=ABC0063016AF57E1C73EF43C8D2212BD&aid=DCF2CC0A6FDC020AEE0DF9FC4D2EC682&yid=67289AFF6305E306&vid=EA389574707BDED3&iid=CA4FD0336C81A37A&sid=27746BCEEE58E9DC&eid=16D8618C6164A3ED&journal_id=1000-324X&journal_name=无机材料学报&referenced_num=0&reference_num=17