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·1298· 精细化工 FINE CHEMICALS 第 35 卷

时，油酸盐分解速率加快，在 1 h 反应时间内油酸 米粒子形貌转变过程遵循粒子内熟化机理。随着反
盐浓度降低较多，磁性纳米粒子沿多个晶面生长， 应温度提高或反应时间延长，磁性纳米粒子由纺锤
最终产物为不规则的纵横比较小的纳米粒子；当反 状纳米粒子转变为具有棱角的不规则状纳米粒子，
应温度继续升高时，油酸盐分解速率更快，在 1 h 进而磁性纳米粒子的棱角逐渐变得模糊并最终形成
反应时间内油酸盐浓度大幅度下降，磁性纳米粒子 球状磁性纳米粒子。本文为同时调控磁性纳米粒子
发生粒子内熟化过程，最终产物为球状纳米粒子。 的形貌、晶体结构和磁性能提供了实验依据，为制
不同反应时间下制备的磁性纳米粒子的透射电 备性能优良的具有尖晶石结构的锰铁氧体纳米粒子
镜图见图 7。由图 7 可知，随着反应时间的延长， 奠定了基础。
磁性纳米粒子的纵横比逐渐降低。当反应时间为
参考文献：
0.5 h 时，所得磁性纳米粒子主要是纺锤状纳米粒子；
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