DC conductivity and AC impedance of Mn doped magnesia alumina spinel (MgAl2-2xMn2xO4) over a large temperature range. Issue 4 (April 2019)

• Record Type: Journal Article
• Authors: Jia, Hongyao; Zhou, Wancheng; Duan, Shichang; Nan, Hanyi; Luo, Fa; Zhu, Dongmei
• Is Part Of: Journal of the European Ceramic Society. Volume 39:Issue 4(2019)
• Page Start: 1251
• Page End: 1256
• Publication Date: 2019-04
• Subjects: Magnesium aluminate oxide (MgAl2O4) -- Dopants/doping -- Conductivity -- Impedance -- Dielectric materials/properties; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2018.11.052
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: MgAl2-2x Mn2x O4 (MAMO) with x = 0-0.12 was synthesized in a single-phase form by solid-state reaction. XRD analysis showed that the samples had the cubic center structure of the Fd-3 m space group. Electrical properties of the samples were studied over the temperature range of 300 K∼1073 K. The results showed that the DC conductivity (σDC ) increased from 10 −11 S/cm at 300 K (MAMO, x = 0) to 10 -3 S/cm at 1073 K (MAMO, x = 0.12). The equivalent circuit of the complex impedance spectra suggested that the relaxation of charge carriers was of non-Debye type. The conduction was mainly caused by grain boundaries and the capacitance was mainly attributed to polarization. The complex permittivity values ( ε' and ε'') were increased by two orders of magnitude with the increase in Mn content and temperature over the measured frequency range (1 Hz-1 MHz). Therefore, doping with Mn could be applied to modify the electrical properties of MAMO at high temperature.