Soft magnetic property and enhanced microwave absorption of nanoparticles of Co0.5Zn0.5Fe2O4 incorporated in MWCNT

• Nanoparticles of Co0.5Zn0.5Fe2O4 are incorporated in the matrix of MWCNT.
• Crystallographic phase and microstructure analysis are carried out.
• Magnetic properties are measured and analyzed.
• Microwave reflection losses are significantly high due to incorporation in MWCNT.

Nanoparticles of Co0.5Zn0.5Fe2O4 (CZFO) are prepared by coprecipitation method where CoCl2·H2O, ZnCl2·6H2O and FeCl3 are used as precursor materials. To enhance the microwave absorption, nanoparticles of CZFO are incorporated in the matrix of multiwall carbon nanotubes (MWCNT). X-ray diffractogram (XRD) and its analysis confirmed the formation of the desired crystallographic phase of the sample. The average crystallite size is evaluated by using the Debye-Scherrer formula. Micrographs observed in high resolution transmission electron microscope confirm the successful incorporation of CZFO in the matrix of MWCNT. Results obtained from the high resolution lattice fringe and selected area electron diffraction patterns are in good agreement with the findings extracted from the XRD analysis. Analysis of Raman spectra confirms the presence of CZFO and MWCNT in the nanocomposite sample. Magnetic properties recorded in SQUID magnetometer confirm the presence of mixed state of superparamagnetic and ferrimagnetic nanoparticles. Reflection losses in X (8–12 GHz) and Ku (12–18 GHz) bands of microwave region are significantly high (~−38.2 dB at 16.9 GHz). High magnetization (~36.5 emu/g at 300 K), low coercive field (~30.1 Oe at 300 K) and high reflection loss of CZFO-MWCNT would be suitable for application in microwave devices.