W.L. Jiao
,
L. Zhang
,
G.C. Yao
金属学报(英文版)
The NiFe2O4 inert anode is synthesized by high-temperature solid-state reaction method using NiO and Fe2O3 as main raw materials and adding MnO2 powder as additive. Archimedes method using water immersion technique is used to measure the sintering performances of samples. The static thermal corrosion rates of samples are measured by weight loss. SEM is employed for the observation of material microstructure, and phase structure of the sample surface after corrosion is determined by XRD. The experimental results indicate that a suitable MnO2 additive content is 2%, while the sintering performance is the best, and the static thermal corrosion rate is the lowest. Because of MnO2 dopant enriching at crystal boundary, the corrosion reaction of molten salt to crystal grain creates Mn2AlO4 phase, which is denser than NiFe2O4 phase, and prevents the cryolite molten salt to penetrate into the inert anode, thus reducing the corrosion.
关键词:
nickel ferrite spinel
,
null
,
null
焦万丽
,
张磊
材料科学与工艺
为了改善NiFe_2O_4纳米粉体气敏性,采用低温固相反应法制备了不同形貌的NiFe_2O_4纳米粉体.以FeSO_4·7H_2O、NiSO_4·6H_2O和NaOH作为反应物,充分研磨制备前驱体,通过先抽滤后600℃热处理和先600℃热处理后抽滤制备了两种NiFe_2O_4纳米粉体,通过X射线衍射和扫描电镜考察了不同制备工艺对纳米晶粒尺寸及形貌的影响.XRD和SEM分析结果表明:两种制备工艺均能生成NiFe_2O_4尖晶石相.先抽滤后热处理制备的NiFe_2O_4纳米粉体颗粒尺寸约为80 nm,颗粒呈立方体结构.而先热处理后抽滤制备的NiFe_2O_4纳米粉体,由于热处理过程中存在Na_2SO_4相,使得NiFe_2O_4纳米粉体颗粒呈圆形片状结构分布,颗粒尺寸为50 nm,厚度约10 nm.
关键词:
低温固相反应法
,
镍铁尖晶石
,
纳米片
,
形貌
