Abstract
A stable Sr4Fe6O13 was prepared as small crystallites by auto-combustion of a sol-gel in air followed by annealing the later at pertinent temperatures. A green sample, as annealed at elevated temperatures, yields a single Sr4Fe6O13 phase of tailored magnetic properties. The structural, morphological, magnetic and electrical properties were investigated by X-ray diffraction, transmission electron microscopy, vibrating sample magnetometer, and broadband dielectric spectrometer. Hard magnetic Sr4Fe6O13 properties arise with saturation magnetization Ms = 12.4 emu/g, coercivity Hc = 3956.7 Oe and squareness 0.512. Studies made at low temperatures reveals Ms decreasing on increasing temperature from 17.5 emu/g at 85 K down to 12.4 emu/g at 305 K, while Hc rises from 1483 Oe at 85 K to 1944 Oe at 305 K. The ac-conductivity follows the Jonscher relation. The dc-conductivity at high temperatures/low frequencies exhibits a plateau and it depends linearly on a characteristic frequency according to the Barton-Nakajima-Namikawa) relation.
Highlights
A stable Sr4Fe6O13 was prepared as small crystallites by auto-combustion of a sol-gel in air followed by annealing the later at pertinent temperatures
A Sr-Fe-O system includes many types of perovskites and perovskite derivatives of widely varied crystalline and magnetic features[8,9,10,11,12]. These types of substances are constructed based on a K2NiF4 shape and involve slab segments of SrFeO3 and SrO, where SrFeO3 is resulting from a KNiF3 cubic perovskite of K2NiF4, and SrO is matching to a NaCl-class KF8
The as-prepared powder was annealed at different temperatures in order to get a single Sr4Fe6O13 phase
Summary
This is a typical behavior of ferromagnetic materials in the moment decreases on increasing thermal energy[33,34]. A gradually increased ε′′ value with increasing temperature describes a thermally induced mobility of charge carriers at these frequencies This confirms a glassy structure of sample S0. In sample S2, which contains three phases, the said plots deviate from the Arrhenius relation, extending a wide peak like behavior This reflects higher ability of ions to transport in promoted conductivity over other samples. The control and data acquisition processes were performed by a WINDETA software[56,57]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
