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 F.D.CORT(E)S-VEGA J.M.YA(N)EZ-LIM(O)N M.D.DURRUTHY-RODR(I)GUEZ
• 来源期刊: 先进陶瓷（英文版）
• 年，卷（期）: 2020,（3）
• 所属期刊栏目: Research Article
• 页码范围: 329-338
• 页数: 10页
• 语种: 英文

摘要

Pure K0.5Na0.5NbO3 (KNN) and KNN doped with Li+ (6％ mole),La3+(1.66％,5％,6％ mole),and Ti4+ (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.sO30),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.