Enhanced Dielectric, Magnetic and EMI Shielding Properties of M-type Barium Hexaferrite and Multi-Walled Carbon Nanotubes Nanocomposite

Abstract

EMI is the new type of pollution which is harmful for both humans and electronic devices and system so there is a need to control this. Among the variety of materials ferrites are most suitable ones. The exceptionally unique magnetic and electric properties of ferrites have always been of strong interest leading to their extensive commercial use. Barium hexaferrite, is one of the materials being used in microwave, electronic and magnetic devices. In this work, doped barium hexaferrite nanoparticles with minimal composition of BaFe12-2xMgxCoxAgxO19 (x=0.0, 0.20, 0.35, 0.50) have been preparedby co-precipitation method with calcination temperature of 9500C. Afterwards BaM/MWCNTs nanocomposite with different percentages of MWCNTs (0.5%, 1%) was synthesized via chemical synthetic route. O-xylene was used as a carrier solvent for uniform and homogenous dispersion MWCNTs and nanoferrites. For the characterization of the samples different characterization techniques such as XRD, SEM, FTIR, impedance analyzer, vibrating sample magnetometer (VSM) and vector network analyzer (VNA) has been performed. The XRD analysis confirmed the successful synthesis of hexaferrite. Debye Scherer equation was used to find out the crystallite size. The attachment of nanoparticles on MWCNTs was confirmed through SEM. The band positions were studied using FTIR. The VSM analysis proved thatthe coercivity and saturation magnetization (Ms)decreased by increasing the dopant ion concentration.At room temperature, the evaluation of dielectric characteristics with frequency change was performed.According to dielectric studies, the concentration of the dopants and the proportion of MWCNTs both improved the dielectric properties. In addition, the maximum absorption loss values of -27.04db and 33.30db at frequency of 8.44GHz and 16GHz has been evaluated for BaFe122x(Mg0.35,Co0.35,Ag0.35)O19/MWCNTs-1%. The prepared samples showed an enhancement in dielectric and magnetic properties proving to be an efficient candidate for many magnetic and electrical applications.