TiN nanofiber metacomposites for efficient electromagnetic wave absorption: Insights on multiple reflections and scattering effects

The exploration of remarkable electromagnetic wave (EMW) absorbing materials with temperature-stable absorbing properties at a wide temperature range holds significant implications for both military operations and civilian life. Herein, the titanium nitride/zirconium oxide/carbon (TiN/ZrO₂/C) ternary nanofiber membranes have been synthesized by electrospinning followed by preoxidation-nitridation process. Thanks to the flexibility of the prepared ceramic membranes, the corresponding metacomposites, characterized by a unique hierarchical structure, were fabricated through the systematic incorporation of subwavelength scale functional units (square fiber membranes) within a polydimethylsiloxane (PDMS) matrix. This approach effectively expanded the transmission path of EMW, contributing to additional multiple reflections and scattering within the system. As a result, when the content of the functional units was as low as 10.0 wt%, the engineered metacomposites exhibited exceptional EMW absorption properties across a broad temperature range (298–573 K). This performance can be attributed to the synergistic effects of optimized impedance matching and enhanced attenuation capacity. Furthermore, the metacomposites achieved a minimum reflection loss (RL) value of −51.7 dB at 453 K, with an effective absorption bandwidth (EAB) spanning 2.3 GHz. This study may serve as a valuable reference for the design of high attenuation capacity EMW absorbing materials under complex variable high-temperature conditions.