Regulating heterogeneous charge distribution/magnetic resonance via ligand constraints for enhanced electromagnetic wave absorption

Abstract

With the rapid development of radar detection systems, the issue of electromagnetic wave stealth has become increasingly prominent. This paper presents a fabrication strategy for a composite material composed of CoFe₂O₄ quantum dots in situ loaded onto CNTs through a multi-ligand combined thermal carbon shock, aiming to optimize multiple loss mechanisms for efficient electromagnetic wave absorption. The CoFe₂O₄ quantum dots serve as loss centers, enhancing the heterogeneous charge distribution and the synergistic effects of magnetic resonance and magnetic exchange due to their supercritical size. Concurrently, the CNTs construct an efficient conductive network, providing a pathway for the free electrons within the CoFe₂O₄ crystals and enhancing conductive loss. The composite achieves an effective bandwidth of 8.02 GHz and a maximum absorption of −52.7 dB at a filling ratio of only 25 %, nearly covering the X and Ku bands. Furthermore, computer simulation techniques indicate that this coating exhibits excellent radar stealth performance on the F-22 Raptor fighter jet, presenting potential for the development and application of a new type of lightweight stealth coating.