【摘要】 以Bi2O3和Fe2O3为铋源和铁源,采用NaNO3和KNO3复合熔盐法快速合成BiFeO3粉体。研究了熔盐温度、熔盐比例、保温时间和冷却速率对合成粉体物相演变的影响,探讨了复合熔盐法合成BiFeO3的形成过程。熔盐温度为500℃时,Bi2O3和Fe2O3间开始反应生成Bi25FeO40相;熔盐温度升高到600℃时,开始生成少量BiFeO3;熔盐温度继续提高到650℃与700℃时,几乎都形成纯相BiFeO3,但仍有微量Bi25FeO40和Bi2Fe4O9相。淬火抑制BiFeO3的分解,系统研究后发现:当熔盐比为5∶1时,700℃保温10 min后淬火合成粉体几乎为纯相BiFeO3。更多还原

【Abstract】 BiFeO3 powders were rapidly synthesized by the molten salt method using Bi2O3 and Fe2O3 as raw materials,NaNO3 and KNO3 as complex molten salt. These effects of molten salt temperature,molten salt ratio,hold time and cooling rate on the phase evolution of BiFeO3 powders had been investigated.And the formation process of BiFeO3 was also discussed during the synthesis by the molten salt method.When the molten salt temperature was 500 ℃,Bi25FeO40 phase was formed throught the reaction of Bi2O3 and Fe2O3. A small amount of BiFeO3 was formed with the molten temperature increasing to 600 ℃.Almost pure BiFeO3 phase was obtained when the molten salt temperature further increased to 650 ℃ and 700 ℃. A trace Bi25FeO40 and Bi2Fe4O9 phase were still observed in the powders. Decomposition of BiFeO3 phase was suppressed by quenching. It was found that almost pure BiFeO3 phase in the quenched powders was synthesized at 700 ℃ for 10 min with the molten ratio of 5∶1.更多还原