浓Fe(OH)_3凝胶水热合成α-Fe_2O_3纳米粒子

Preparation of α-Fe_2O_3 Nano-particles from Condensed Fe(OH)_3 Gel by Hydrothermal Method

研究了以Fe(NO3)3为原料加NH3.H2O中和得到的Fe(OH)3浓凝胶作前驱物,水热合成α-Fe2O3纳米粒子时,前驱物pH值对产物形貌的控制作用.当pH值为3、5时,粒子形貌为近球形多孔结构;当pH值为7时,为菱形粒子;当pH值为9时,粒子形貌由菱形向球形转变.在上述条件下得到的产物为粒径小且分布均匀的单晶粒子.此外,还分析了前驱物pH值对产物形貌及大小的控制作用原理.

The effects of pH values of precursors using Fe（NO3） 3 as materials neutralized by NH3·H2O to form Fe（OH） condensed gel on the morphology of α-Fe2O3 nano - particles prepared by hydrothermal method were studied. When pH value was 3 or 5, the particles were spherical with porous structure. When pH value was 7, the particles were rhombohedral, When pH value was 9, the morphology of particles converted from rhombohedral to spherical shape. The products were single crystal particles and were distributed uniformly with small particles under the above experimental conditions. The effect of pH values of precursors on the morphology and sizes of particles was also analyzed.