Elaboration and Characterization of Materials from the LaMnO₃–BiMnO₃ Binary System

Abstract

The study of the La(1‐x)BixMnO3 system is conducted using X‐ray diffraction (XRD) and electrical measurements. A continuous solid solution is evidenced for the LaMnO3 rich part of this system (x ≤ 0.6). According to the analyses of XRD results, a rhombohedral symmetry (R3¯c) is observed for x ≤ 0.4 and a cubic structure for x = 0.5. The structural study allows to determine an increase in the mean perovskite lattice parameter, together with a decrease in the rhombohedral angle up to a cubic symmetry for x = 0.5. For x > 0.6, the system is no more single‐phased. Impedance measurements are conducted for ceramics in a wide‐frequency range (100 Hz–1 MHz), between room temperature and 800 °C. The exponential decrease in the alternative current (AC) conductivities (σAC) and the room temperature values correspond to a semiconducting behavior. Direct current (DC) conductivity measurements (σDC) are also performed below room temperature (25 K < T < 300 K). The results evidence for a metal–insulator phase transition. For the exponential part of the σDC curves, the gap energy is between 0.1 and 0.2 eV, confirming the semiconductor behavior of these materials.

Annealing-Dependent Morphotropic Phase Boundary in the BiMg0.5Ti0.5O3–BiZn0.5Ti0.5O3 Perovskite System

“…At the same time, many efforts are focused on discovering new lead-free perovskite systems with MPB. Attempting to reveal new compositions, researchers explore multicomponent systems, in which one or more end members do not have a stable modification at ambient pressure (e.g., BiScO 3 [ 13 ], BiMnO 3 [ 14 ] and BiCrO 3 [ 15 ]). In some cases, the compositions corresponding to MPB in such systems can be prepared using conventional routes; the majority of cases require the application of high-pressure synthesis.…”

The Structural, Impedance and Dielectric a Ferrite Core of Iron Manganite and Its Composite

“…The electrical resistivity of nickel zinc nano ferrites is highly dependent on the size of the crystallinity and with increasing frequency, the dielectric constant decreases [5,6], and the value of tan 𝜕 also decreases [7,8]. The perovskite LaMnO3 compound, with increasing frequency will also experience a decrease in impedance, dielectric and tan 𝜕 constants [9], and also their electrical conductivity [10].…”

“…Several methods have been used for the sample preparation process, for example solid reaction [1,10], sono-chemical [2], sol-gel auto-combustion [4,6], coprecipitation [5], the polymerizable complex [9]. Of the several methods, the solid reaction is the easiest and cheapest method.…”