Novel mechanochemical process for synthesis of magnetite nanoparticles using coprecipitation method

作者：Iwasaki Tomohiro^*; Kosaka Kazunori; Yabuuchi Tomoya; Watano Satoru; Yanagida Takeshi; Kawai Tomoji

来源：Advanced Powder Technology, 2009, 20(6): 521-528.

DOI：10.1016/j.apt.2009.06.002

• Mechanochemical effect
• Nanomaterials
• Ball-milling
• Numerical analysis
• Magnetic materials

A novel coprecipitition method using a high mechanical energy field as the synthesis reaction system of magnetite (Fe(3)O(4)) has been developed for preparing the superparamagnetic Fe(3)O(4) nanoparticles with high crystallinity in water system. In the synthesis process, the suspension containing the precipitates of ferrous hydroxide and goethite was treated in a tumbling ball mill under a cooling condition. The mechanical energy generated by collision of ball media promoted the Fe(3)O(4) formation reaction and simultaneously crystallized the formed Fe(3)O(4) nanoparticles without using any conventional heating techniques by means of the mechanochemical effect. The collision energy of ball media was numerically analyzed by discrete element simulation of their motion in the ball mill. Size, crystallinity and magnetization of the Fe(3)O(4) nanoparticles obtained under different ball-milling conditions were almost the same regardless of the amount of the collision energy. However, the reaction rate of Fe(3)O(4) formation increased with the collision energy, which was analogous to increase of the reaction rate caused by increase of the heat energy applied to the reaction system. The reaction rate depended strongly on the number of collisions with the energy larger than a threshold value corresponding to the activation energy in this reaction system.

• 出版日期2009-11