Effect of additive on synthesis of MnZn ferrite nanocrystal by hydrothermal crystallization
来源期刊:中南大学学报(英文版)2003年第1期
论文作者:桑商斌 古映莹 黄可龙
文章页码:38 - 43
Key words:MnZn ferrite nanocrystal; growth unit; hydrothermal process mechanism; additive
Abstract: The effect of additive RCOONa on the formation of MnZn ferrite homogeneous coprecipitation precursor was studied in this paper. The action of additive in the MnZn ferrite hydrothermal crystallization process was investigated according to crystal field theory and crystal growth unit theory.And the growth unit formation process was presented and its structure was illustrated. The results show that the precursor of MnZn ferrite is a colloidal mixture composed of Zn(OH)2, Fe(OH) 2, Mn(OH) 2, MnO(OH) , MnO2·xH2O and so on, and dissolves in solution in the form of hydroxyl coordination tetrahedron and octahedron such as Zn(OH) 2-4, Fe(OH) 2-4, Fe(OH)4-6,Fe(OH)-4, Fe(OH)3-6,Mn(OH)2-4,Mn(OH)3-6etc., and the growth unit is formed by combination of the coordination polyhedra subsequently in the hydrothermal precess. The additive is beneficial to the formation of homogeneous precursor and has dispersive effect on the aggregation of the crystal growth unit by forming associate with hydrogen bond, which is beneficial to the synthesis of the pure product with a tiny size and a narrow size distribution.