One-step rapid achieving O-SWCNHs@SiO2 core-shell heterostructures with tunable electromagnetic absorption performance via arc plasma

Core-shell heterostructures are promising functional materials with prospective applications in the electromagnetic wave (EMW) absorption field. Herein, according to the bottom-up synthesis approach, the OSWCNHs@SiO2 core-shell nanoarchitecture materials with ultra-low bulk density (23-32 mg & sdot;cm- 3) are rapidly in situ synthesis by using DC arc plasma. The SiO2 is wrapped flatly on the outer surface of the O-SWCNHs spheres-core, forming a unique heterostructure. The introduction of SiO2 shell causes the ample interfacial of SWCNHs/SiO2 that regulates interfacial polarization and impedance matching. Meanwhile, the in-situ doping of oxygen and silicon atoms enhances the dipole polarization. The SWCNHs@SiO2 possesses excellent tunable EMW absorption performance. The minimum reflection loss (RLmin) peak can move from a high frequency (13.9 GHz, -61.78 dB) to a low frequency (6.48 GHz, -59.85 dB), and the RL curve lower than -10 dB can cover 88.8 % (3.8-18 GHz) of the measuring frequency. The effective bandwidth and RL are superior to most composite absorbers with SWCNHs or SiO2 components. Overall, this work presents a simple and fast method for creating core-shell heterostructure that may be used as highly effective lightweight EMW absorbers with adjustable absorption performance.