Synergistic effect of silica coated porous rodlike nickel ferrite and multiwalled carbon nanotube with improved electromagnetic wave absorption performance

Abstract

In this study, multiwalled carbon nanotube (MWCNT) anchored on the surface of silica coated porous rodlike nickel ferrite (NiFe2O4@SiO2) composite was fabricated, and its structure, composition, magnetic and electromagnetic (EM) wave absorption properties were studied. High-performance EM wave absorption properties of the ternary composite can be regulated by the coating thickness and the content of the absorber. The reflection loss (RL) was optimized to −67.8 dB at the matching thickness of 1.9 mm, and the effective absorption bandwidth (RL ≤ −10 dB) was 4.5 GHz (13.5–18 GHz) at the coating thickness of only 1.5 mm with the filler loading 40 wt%. The effective bandwidth can reach 5.3 GHz (12.7–18 GHz) at the coating thickness of only 2.2 mm with the filler loading 30 wt%. The broadband absorption, thin thickness, strong absorption and adjustable absorption properties endow NiFe2O4@SiO2/MWCNT composite with extensive prospects for EM wave absorption.