First Study on the Formation of Strontium Ferrite Thin Films on Functionalized Multi-Walled Carbon Nanotube

Abstract

Substituted strontium ferrite (SrFe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12-x</sub> (Cr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> ) <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">19</sub> ) thin films were formed along the surface of multiwalled carbon nanotubes (MWCNTs). Mössbauer spectroscopy indicates that the substituted cations preferentially occupy the 12 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> sites. X-ray diffraction (XRD), transmission electron microscope (TEM), field emission scanning electron microscope (FE-SEM), vibrating sample magnetometer (VSM), and vector network analyzer were used to analyze the structure, static, and high-frequency magnetic properties of the prepared samples. It was found that with an increase in substitution content, the saturation of magnetization decreases while the coercivity increases. The CNTs could enhance the real and imaginary parts of permittivity of ferrites. With an increase in volume percentage of MWCNTs, the reflection loss values were increased.