Construction of TiO2 nanointerfaces in Yb2Si2O7 ceramics with adjustable electromagnetic wave absorption and high-temperature stability

Abstract

Due to the poor electromagnetic (EM) wave attenuation capability and relatively large bandgap of rare-earth silicate materials, their application as EM wave attenuation materials is adversely affected. In this work, TiO₂ was deposited onto the surface of porous Yb₂Si₂O₇ using a precipitation process followed by calcination. A transition from TiO₂ nanorods to nanowires resulted in a flower-like three-dimensional (3D) network structure, effectively modulating the dielectric and EM wave-absorbing properties. The TiO₂/Yb₂Si₂O₇ ceramic (YT-3 sample) with a TiO₂ nanowire content of 20.1 wt% achieved a minimum reflection loss (RL_min) of −21.1 dB at 2.3 mm and an effective absorption bandwidth (EAB) of 2.6 GHz at a thickness of 2.5 mm. Furthermore, the EAB fully covered the X-band at thickness ranging from 2.0 to 4.10 mm. The radar cross-section of the YT-3 sample significantly decreased by 21.5 dBm². This improvement likely attributed to the 3D porous structure formed by the TiO₂ nanowires, which improved the impedance matching and electrical conductivity while increasing both homogeneous interfaces and heterointerfaces. This enhancement facilitated electron transfer and hopping, amplified polarization and conduction losses and promoted multiple EM wave reflections and scattering. Additionally, the weight variation of the YT-3 sample was <0.48 % in the range of 25–1400 °C, demonstrating excellent high-temperature stability. These results advances to the development of Yb₂Si₂O₇-based wave-absorbing materials for achieving effective EM wave absorption in high-temperature environments.