核-壳结构SrFe_(12)O_(19)-NiFe_2O_4复合纳米粉体的吸波性能  

Absorbing properties investigation of SrFe_(12)O_(19)-NiFe_2O_4 composite nanopowders with core-shell structure

作　　者：陈映杉[1,2] 冯旺军[1,2] 李翠环[2] 李瑞山[1,2] 范瑞[2] 杨华[1,2] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,兰州730050 [2]兰州理工大学理学院,兰州730050

出　　处：《复合材料学报》2012年第1期111-116,共6页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(50962009);教育部重点项目(0910ZBA017);甘肃省自然科学基金(1014RJZA015,0916RJZA023)

摘　　要：以Fe(NO3)3、Ni(NO3)2和Sr(NO3)2为主要原料,通过两步柠檬酸盐溶胶-凝胶法,制备出核-壳结构SrFe12O19-NiFe2O4磁性纳米复合粉体。采用XRD、TEM、VSM及矢量网络分析仪对合成的粉体的结构、形貌及吸波性能进行了分析研究。结果表明,复合粉体的相结构与NiFe2O4含量有关,当SrFe12O19与NiFe2O4的质量比为1∶2、烧结温度为1050℃时,复合纳米粉体的相与NiFe2O4接近,核-壳结构SrFe12O19-NiFe2O4纳米复合粉体的饱和磁化强度(Ms)(51.4emu/g)比单体SrFe12O19纳米粉体(42.6emu/g)的大;但矫顽力(Hc)(336Oe)比单体SrFe12O19纳米粉体的小,在SrFe12O19与NiFe2O4的矫顽力5395～160Oe之间。在频率为8～18GHz范围内,微波吸收逐渐增强,当频率为12GHz时,SrFe12O19-NiFe2O4纳米复合粉体的微波吸收达到最大值-9.7dB,是一种性能优良的吸波材料。The nanoscale magnetic composite powders SrFe12O19-NiFe2 04 with core-shell structure were prepared by two- step citrate sol - gel, with Fe（NO3）3 Ni（NO3）2 and Sr（NO3）2 as the main materials. The XRD, TEM, VSM and vector network analyzer were used to analyze the structure, feature and absorbing quality of the nano-powder. The results show that the phase structure of the powder is related to the content of NiFe204, when the mass ratio of SrFel2Ol9 to NiFe2O4 is 1 ： 2 and calcined temperature is 1050℃, the phase of the powder is similar than that of NiFe204, the magnetization（Ms）of SrFe12 O19 and the coreshell nano-powde raises from 42.6 emu/g to 51.4 emu/g, and the coercivity（Hc） is 336 Oe, which is between that of SrFe12O19 （5395 Oe） and NiFe2O4 （160 Oe）. The absorbing quality is enhanced when the frequency is from 8 GHz to 18 GHz. When the frequency is 12 GHz, the microwave absorption can reach maximum point which is -9. 7 dB. The composite nano- powder is an excellent absorbing material.

关 键 词：SrFe12O19 NIFE2O4 磁性纳米粉体 核-壳结构 吸波性能 

分 类 号：TB332[一般工业技术—材料科学与工程]