pH值和灼烧温度对Fe_2O_3粒子结构及磁性能的影响

以FeCl3为原料,尿素为添加剂,NaOH为pH值调节剂,采用sol-gel法制备出前驱体Fe(OH)3胶液。将其烘干、高温灼烧制备了磁性粒子Fe2O3。研究了pH值和灼烧温度对Fe2O3相成分和磁性能的影响。结果表明:当pH值为3,4,灼烧温度为450℃时,产物为高纯度γ-Fe2O3,饱和磁化强度Ms为12.8A·m2·kg-1;当pH值为7,灼烧温度为500℃时,产物是单相的α-Fe2O3,结晶完好,产物的饱和磁化强度Ms为3.1A·m2·kg-1。

Effects of pH value and calcining temperature on the structure and magnetic property of Fe2O3 particles

Using FeCl3 as raw materials,urea as additive and NaOH as pH value regulator,the precursor Fe(OH)3 glue was produced by the sol-gel method.And then obtained glues were dried and calcined to prepare magnetic Fe2O3 particles.The effects of pH value and calcining temperature on their structure and magnetic property were studied.The results indicate that when pH value is 3 and 4,calcining temperature is 450 ℃,obtained product is high purity γ-Fe2O3,and its saturation magnetization is 12.8 A·m2·kg-1;if pH value and calcining temperature are 7 and 500 ℃,respectively,the product obtained is a single phase α-Fe2O3 having good crystalline,while its saturation magnetization is 3.1 A·m2·kg-1.