Superparamagnetic nanocubes of Co and Cu co-doped Mn-based ferrites as microwave absorbing material

Abstract

The requirement in resolving electromagnetic (EM) problems in stealth warhead technologies are excellent absorption ability, lightweight, and thin dimensions. In this direction, this study provides a straightforward hydrothermal one-pot method to synthesize superparamagnetic Mn-based ferrite co-doped with Co and Cu (MCCF), and the article presents its microwave absorption properties. Using cutting-edge techniques, the MCCF nanocomposite phase structure, morphological, superparamagnetic, and microwave absorption properties were measured and analyzed. MCCF-822 ferrite shows superparamagnetic properties simultaneously with a high Ms value 71.4 emu/g. Vector network analysis of MCCF-822 with 70 wt% loading demonstrates an effective absorption bandwidth (EAB) of 5.2 GHz with a maximum reflection loss (RLmax) of −19.2 dB at 2 mm thickness, and it spans almost 92.77 % frequency region (3.3–18 GHz range with RL < −10 dB) by varying thickness 1.7 mm–6 mm. At 60 wt% loading, it covers the whole X & Ku band with a thickness range from 2 to 9 mm with a good EAB of 4.3 GHz at 2.5 mm thickness with RLmax of −16 dB. The dual absorption bands are also present in MCCF-613, which increases the EAB with RLmax −52.99 dB at 9 mm, fulfilling the superparamagnetic properties. Thus, MCCF-822 is proposed as a cost-effective superior ferrite nanocomposite for microwave absorption applications.