Study of the structural,ferroelectric,dielectric,and pyroelectric properties of the K0.5Na0.5NbO3 system doped with Li+,La3+,and Ti4+  

作　　者：C.MONTERO-TAVERA M.D.DURRUTHY-RODRiGUEZ F.D.CORTES-VEGA J.M.YANEZ-LIMON 

机构地区：[1]Center for Research and Advanced Studies of IPN,Campus Queretaro,Mexico [2]National Evangelical University,Paseo de los Periodistas#54,Ensanche Miraflores,Santo Domingo,Distrito Nacional,Repiblica Dominicana

出　　处：《Journal of Advanced Ceramics》2020年第3期329-338,共10页先进陶瓷（英文）

基　　金：The authors express their thanks to CONACYT for funding this research through projects CB-240460 and LN-295261,and to LIDTRA for the facilities in the use of experimental infrastructure.

摘　　要：Pure Ko.sNao sNbO3(KNN)and KNN doped with Lit(6%mole),Lat(1.66%,5%,6%mole),and Ti+t(10%mole)were prepared by mixture of oxides using high-energy milling and conventional solid-state reaction.The effects of the dopant on the physical properties of pure KNN have been evaluated based on the structural,ferroelectric,pyroelectric,and dielectric measurements.The XRD measurements show that KNN pure sample contains a mixture of monoclinic and orthorhombic crystalline phases,with a slightly higher concentration of monoclinic phase.In contrast,all doped samples show a higher concentration of the orthorhombic phase,as well as the presence of a secondary phase(K6Nb10.8O3o),also detected by Raman measurements.The samples with a higher concentration of this secondary phase,also present greater dielectric losses and lower values of remnant polarization.The dielectric measurements allowed us to detect temperatures of structural transitions(orthorhombic-tetragonal,O-T)previous to the ferroelectric paraelectric transition(tetragonal-cubic,T-C),and also in this set of samples,a direct correlation was found between the values of remnant polarization and the corresponding pyroelectric signal response.

关 键 词：K0.5Na0.5NbO3(KNN) LEAD-FREE solid-state reaction structural properties pyroelectric properties dielectric properties Li La Ti doping elements 

分 类 号：TQ174.1[化学工程—陶瓷工业]