摘要
使用溶胶-凝胶法原位制备了具有镶嵌结构的0-3型Na_(0.5)Bi_(0.5)TiO_(3)-CoFe_(2)O_(4)(NBT-CFO)复相多铁性陶瓷,并研究其电、磁性能。通过TG-DTA、XRD等表征手段研究了干凝胶的结晶过程,利用CFO与NBT的差异化结晶温度设计了分步煅烧结晶工艺并得到粒径45 nm的NBT-CFO纳米粉体,并烧结得到具有镶嵌结构的0.9NBT-0.1CFO(0.1CFO-SG)复相陶瓷,陶瓷中CFO晶粒均匀分布在NBT晶粒内部。与使用机械混合法制备的复相陶瓷(0.1CFO-MM)相比,具有镶嵌结构的0.1CFO-SG复相陶瓷在250 Hz~1 MHz频率范围内的室温介电损耗均更低,250 Hz时其损耗只有前者的30%。介电温谱、阻抗谱与模谱分析表明,0.1CFO-SG复相陶瓷在350~650℃温区内表现出由铁电-铁磁相界面极化造成的介电弛豫行为,其激活能为0.77 eV。镶嵌结构使0.1CFO-SG复相陶瓷在室温下具有更大的剩余极化和更高的抗击穿场强,提高了其铁电性能。
The 0-3 type Na_(0.5)Bi_(0.5)TiO_(3)-CoFe_(2)O_(4)(NBT-CFO)composite multiferroic ceramics with embedded structures were prepared by in-situ sol-gel method,and their electrical and magnetic properties were studied.The crystallization behavior was studied by TG-DTA and XRD.Based on the difference between the crystallization temperatures of CFO and NBT,a two-step calcination process was designed to obtain NBT-CFO nano-powders with the average size of 45 nm.0.9NBT-0.1CFO(0.1CFO-SG)composite ceramics sintered using the nano-powders have embedded structures,where the CFO grains are uniformly distributed inside the NBT grains.Compared to the composite ceramics prepared by the mechanical mixing method,the 0.1CFO-SG composite ceramics with embedded structures have lower dielectric loss in 250 Hz~1 MHz at room temperature,and the loss at 250 Hz is only 30%of the former.The temperature dependent relative permittivities,impedance spectrum and mode spectrum show that composite ceramics with embedded structures exhibit dielectric relaxation behavior caused by the interfacial polarization between NBT and CFO at 350~650℃,and the activation energy is 0.77 eV.0.1CFO-SG composite ceramics with embedded structures have larger remanent polarization,higher breakdown strength and greater ferroelectric performances at room temperature.
作者
李方喆
柯华
张洪军
邢苗
田晶鑫
唐晓慧
贾德昌
周玉
Li Fangzhe;Ke Hua;Zhang Hongjun;Xing Miao;Tian Jingxin;Tang Xiaohui;Jia Dechang;Zhou Yu(Institute for Advanced Ceramics,School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150080,China;Key Laboratory of Advanced Structural-Functional Integration Materials&Green Manufacturing Technology,Harbin 150001,China;School of Instrument Science and Engineering,Harbin Institute of Technology,Harbin 150080,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2022年第3期1063-1071,共9页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51772065,5201101737,52002093)
中央高校基本科研业务费专项资金(HIT.NSRIF.2020102)
黑龙江省博士后面上项目(LBH-Z19164)
哈尔滨工业大学世界顶尖大学战略合作计划(LY_DJ1596414013121)。
关键词
复合材料
多铁性陶瓷
界面
介电弛豫
阻抗谱
composite materials
multiferroic ceramics
interface
dielectric relaxation
impedance spectrum
