Joule heating-driven ultrafast synthesis of (Fe <sub>1− <i>x</i> </sub>Mn <sub> <i>x</i> </sub>) <sub>2</sub>AlB <sub>2</sub> and its electromagnetic wave absorption properties
Yuhang Bai, Zelong Yao, Yang Yang, Jingrui Li, Jia Liu, Peipei Wang, Huiling Du, Xing Zhao, Laifei Cheng
Abstract
Defect engineering enables the efficient management of electromagnetic parameters and the enhancement of electromagnetic wave (EMW) absorption. In this study, (Fe<sub>1−<i>x</i></sub>Mn<sub><i>x</i></sub>)<sub>2</sub>AlB<sub>2</sub> transition metal boride (MAB) phases with a layered structure were prepared via Joule heating-driven ultrafast synthesis, and their EMW absorption properties were investigated. The experimental results demonstrate that the incorporation of Mn atoms at the M site can effectively modulate the impedance matching and EMW absorption properties of the material through the introduction of defects and lattice distortions. Notably, (Fe<sub>0.3</sub>Mn<sub>0.7</sub>)<sub>2</sub>AlB<sub>2</sub> exhibits a reflection loss as high as −47.8 dB at 12.24 GHz, with a maximum effective absorption bandwidth of 4.16 GHz (10.24–14.40 GHz) at an ultrasmall thickness of 1.5 mm. This study provides a promising avenue for the development of excellent microwave-absorbing materials, which are essential for meeting the evolving requirements of advanced electronics. Additionally, this work offers a paradigm for enhancing other properties of MAB phases through defect engineering.