铁系纳米晶体β-FeOOH， a -Fe2O3 具有很广泛的应用背景，越来越受到人们的关注。本论文对比了目前常见的各种干湿法制备方法后，以均匀成核理论为指导，成功制备了β-FeOOH 和a-Fe203 纳米晶体。XRD 及SEM 的分析结果表明产物均为棒状，两者形态和尺寸非常接近，长轴约60nm ，短轴约10 -1 3nm，横纵比约为1 : 5，且晶粒尺寸分布比较均匀。进一步的分析表明β-FeOOH 纳米棒沿［001］方向拉长而a-Fe203 纳米棒沿［l11］方向拉长。利用紫外-可见分光光度计分析了产物，观测到了吸收光谱中的蓝移现象；对比分析了制备过程中反应温度、超声波、热分解温度等条件对产物的影响，指出了反应过程中PH 值的变化特殊的原因，特别分析了β-FeOOH表面的有机物包覆层在前驱体生长和热分解制备a-Fe203 过程中的保护作用。

β-FeOOH and a–Fe2O3 nanocrystals have been paid much attention due to their many useful properties. β-FeOOH and a–Fe2O3 nanocrystals were prepared based on homogeneous nucleation theory. The nanocrystals were characterized by X-ray powder Diffraction (XRD), S canning Electron Microscope (SEM) and Ultraviolet Visible Absorption Apectroscopy. Both of β-Fe00H and a–Fe2O3 nanocrystals were rod like with about 60nm long and 1 0 to 1 3nm in diameter. The further analyses show that the β-Fe00H rods elongated along [ 0011 axis and the a–Fe2O3 elongated along [111] axis. The rods showed uniform size distribution. Blue shift of band gap absorption was observed. The change of PH during growth of β-Fe00H, the effects of growth temperature and ultrasonic were discussed . The thermed decomposing temperature and the protection of organic surfactant to a–Fe2O3 rods were also discussed.