Polydopamine-Modified Polyaniline/Nanodiamond Ternary Hybrids with Brain Fold-like Surface for Enhanced Dual Band Electromagnetic Absorption

Polydopamine-modified nanodiamond/polyaniline ternary hybrids with brain fold-like surfaces were synthesized through an in situ polymerization. The surface morphology and structure were characterized by X-ray diffraction analysis and scanning and transmission electron microscopy. In the ternary hybrids, the dispersion of nanodiamond was improved. Meanwhile, a uniform brain fold-like surface could form after adding a certain amount of dopamine. The hybrid interactions were confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The hydrogen bonding interactions as well as the π–π hybrid interactions dominate the tannery hybridization, which could introduce a more asymmetrical polarization center and interface. The optimized polydopamine-modified nanodiamond/polyaniline ternary hybrid exhibited obvious dual band enhanced electromagnetic absorption (−24.3 dB, 5.0 GHz and −23.5 dB, 15.9 GHz). The electromagnetic losses result from the surface brain fold-like structure, the well dispersed nanodiamond size effect, and the ternary hybridization. Our finding indicates this material has great potential interest in high performance electromagnetic selective absorption materials covering the C band and Ku band.