Modulating morphologies and electromagnetic wave absorption performances of 3d-4f PBA derivatives with transition metal ions

Prussian blue analog (PBA) derivatives are widely utilized as high-performance electromagnetic wave absorption (EMWA) materials. Despite their potential, the specific impact of different metal ions on the morphology and EMWA performance of 3d-4f PBAs has remained unclear. Herein, using a coprecipitation method and different transition metal ions, we synthesized DyM(CN)6 (M = Fe, Co) PBAs of different morphologies: six-petal flower-like structure for DyFe(CN)6 and an elliptical seed shape for DyCo(CN)6. Upon annealing, Dy2O3/Fe@CNT and Dy2O3/Co@CNT composites (CNT = carbon nanotube) maintaining their original shapes were prepared. The Dy2O3/Co@CNT composite, in particular, showed excellent EMWA properties with an RLmin of −48.32 dB at 15.44 GHz and an EAB of 5.68 GHz at an ultrathin thickness of only 1.75 mm. This performance is attributed to optimized impedance matching and synergistic magnetic-dielectric effects, along with interfacial polarization from Dy2O3, Co, and CNT interfaces. The simulated radar cross-section (RCS) confirms the excellent EMW attenuation capability of Dy2O3/Co@CNT and shows immense potential for practical application. This work offers a new approach to developing high-performance EMWA materials of 3d-4f PBA derivatives.