Effect of Bi-substitution into the A-site of multiferroic La_0.8Ca_0.2FeO₃on structural, electrical and dielectric properties

Abstract

(La0.8Ca0.2)1−xBixFeO3 (x = 0.00, 0.05, 0.10, 0.15 and 0.20) (LCBFO) multiferroic compounds have been prepared by the sol–gel method and calcined at 800 °C.

Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine

“…The Williamson–Hall method, for determination of the β parameter, has the advantage to the Debye–Scherrer method of taking into account the strain contribution to the X-ray line broadening [ 52 ], i.e., , where is obtained from the Debye–Scherrer equation (Equation (1)) and , being a coefficient related to the crystallite strain effect. Therefore, it is possible to determine the crystallite size ( ) and the lattice microstrain by the slope of “ “ in function of “ ” [ 53 ] and the interception of the linearization line at the origin, according to Equation (2): …”

“…The crystallite sizes, determined by the Williamson–Hall method, for the samples heat-treated at 600 and 800 °C, are smaller than 100 nm, being smaller for the sample heat-treated at 800 °C. In addition, in this sample, the strain value (slope Equation (2)) is negative, meaning that it presents a compressive strain, while if the value is positive indicates the presence of a tensile strain (samples PCW_600 °C and PCW_1000 °C) [ 53 ].…”

Structural, morphological, Raman, dielectric and electrical properties of La1−2xBaxBixFeO3 (0.00 ≤ x ≤ 0.20) compounds

“…Moreover, the resistance of the grain boundary contribution is higher than of the grain one which is in good agreement with previous results of ferroic perovskite materials. 51,52 Also, we can deduce that the values of the alpha ( α ) parameter are around the unite for all compounds at the used temperature range which means that the QPE element is very close to a capacitance. We have plotted the logarithmic resistance values of both contributions as function of the inverse of temperature (1/ T ) with respect of the Arrhenius power law eqn (4) , in order to evaluate the effect of the substitution on the activation energy corresponding to grain and grain boundary contributions.…”

An effective strategy for the development of multiferroic composite nanostructures with enhanced magnetoelectric coupling performance: a perovskite–spinel approach

“…However, there is a change in the dielectric relaxation process, as M'' max peaks shifts towards the higher frequencies when the concentration of NFO increases. The peak, at low frequencies is ascribed to grains contribution and at high frequencies is attributed to grain boundaries 2 . The frequency at which M'' is maximum is known as relaxation frequency.…”