Fabrication of Single-crystal Porous Hedgehog-sphere Structured TiO 2 -rGO Aerogel as a Broadband and Strong Absorption Electromagnetic Wave Absorber

Abstract

Excessive conductivity of graphene oxide (GO) often contributes to inferior impedance matching performance of material, which extremely imposes restrictions on the field of electromagnetic wave (EMW) absorption. A highly fruitful strategy to assure the material possess both distinguished EMW attenuation and impedance matching capabilities is to combine GO with some other substances with low conductivity. In this study, TiO 2 microspheres with single-crystal mesoporous hedgehog-ball structure are fabricated and anchored on GO nanosheets via a facile hydrothermal strategy. The electromagnetic parameters of the composites are regulated through adjusting the mass ratio of TiO 2 to GO, and thereby precisely regulating the EMW absorbing properties. Consequently, the fabricated TiO 2 -rGO 1:1 sample exhibits prominent EMW absorption capacity with a broad effective absorption bandwidth (EAB) of 8.08 GHz and strong reflection loss (RL min ) of -44.7 dB. The extraordinary EMW absorption performances are attributed to the synergistic effect of TiO 2 and GO, including abundant conduction loss and polarization loss. In addition, quantitative analyses of conduction loss and polarization loss of the fabricated composites are conducted to provide clear guidance for our future work. This work not only provides guidance and afflatus for the structural design of EMW absorbers but also discloses the relationship between conduction loss and polarization loss of materials.