Crystal structure, infrared spectra and microwave dielectric properties of Li4Mg3[Ti1-x(Mg1/3Nb2/3)x]2O9 (x = 0−0.5) ceramics. Issue 18 (15th December 2018)

• Record Type: Journal Article
• Authors: Xing, C.F.; Wu, H.T.
• Is Part Of: Ceramics international. Volume 44:Issue 18(2018)
• Page Start: 23329
• Page End: 23333
• Publication Date: 2018-12-15
• Subjects: Li4Mg3[Ti1-x(Mg1/3Nb2/3)x]2O9 -- Infrared spectra -- Microwave dielectric properties; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.09.085
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: A series of Li4 Mg3 [Ti1-x (Mg1/3 Nb2/3 )x ]2 O9 (LMT1-x (MN)x O) (x = 0–0.5) ceramics were prepared by the solid-state reaction method in this work. The effects of (Mg1/3 Nb2/3 )-substitution on the crystal structure, sintering behavior and microwave dielectric properties of Li4 Mg3 Ti2 O9 ceramics were investigated for the first time. The XRD patterns revealed that LMT1-x (MN)x O samples exhibited a single Li4 Mg3 Ti2 O9 phase with space group Fm-3m. The results indicated that the (Mg1/3 Nb2/3 )-substitution could improve dielectric properties. Especially, the dielectric constant of LMT1-x (MN)x O (x = 0.4) samples sintered at 1450 °C was influenced by the polar optical phonons, which could be proved by the analysis of IR reflectivity spectrum. Typically, the optimum microwave dielectric properties of ε r = 16.83, Q · f = 144, 350 GHz and τ f = −3.05 ppm/°C were achieved in Li4 Mg3 [Ti0.6 (Mg1/3 Nb2/3 )0.4 ]2 O9 ceramics sintered at 1450 °C.