摘要
采用成核/晶化隔离法制备出一系列Ni2+-Co2+-Fe2+-Fe3+-SO42--LDHs层状前驱体,焙烧后得到尖晶石型铁氧体Ni1-xCoxFe2O4。对样品的晶体结构及元素组成进行分析,结果表明,制得的尖晶石型铁氧体Ni1-xCoxFe2O4晶体结构优良,元素组成可控性强。分别将Ni1-xCoxFe2O4、NiFe2O4和CoFe2O4的磁学性能参数的理论混合值和机械混合值随x[x=n(Co)∶n(Ni)]的变化情况进行比较,发现Ni1-xCoxFe2O4的磁学性能并不是简单的NiFe2O4和CoFe2O4磁学性能的加合,Co和Ni原子之间存在着一定的协同效应,且当x为0.2时,Ni1-xCoxFe2O4的磁学性能最佳。
Layered double hydroxides （LDHs） precursors Ni^2＋-Co^2＋-Fe^2＋-Fe^3＋-SO4^2--LDHs were synthesized by a method consisting of separate nucleation and aging steps （SNAS）. Ni1-x CoxFe2O4 spinel ferrites were obtained after calcination at 900 ℃. XRD and ICP results indicated that Ni1 -x CoxFe2O4 spinel ferrites had fine crystal structure and controllable composition. In addition, preferable linear fitting were found between the magnetic data of Ni1-xCoxFe2O4 and the value of x[x = n（ Co）： n（Ni） ] . The practical magnetic values of Ni1-xCoxFe2O4 were higher than theoretically mixed and mechanically mixed values of NiFe2O4 and CoFe2O4, which indicated that there was a synergistic effect on Co and Ni which resulted in better magnetic properties of Ni1-xCoxFe2O4. When x equaled to 0.2, Ni1-xCoxFe2O4 exhibited the best magnetic properties.
出处
《工业催化》
CAS
2008年第10期46-50,共5页
Industrial Catalysis
关键词
催化化学
铁氧体
磁学性能
LDHS
成核/晶化隔离法
协同效应
catalytic chemistry
ferrite
magnetic properties
LDHs
separate nucleation and aging steps （SNAS）
synergistic effect
