Ternary layered boride MoAlB: A novel thermo-regulation microwave absorbing ceramic material

In the context of the fifth-generation (5G) smart era, the demand for electromagnetic wave (EMW)-absorbing materials has become increasingly prominent, so it is necessary to explore promising candidate materials. This work focuses on the exploration of the material absorbing properties of a MoAlB MAB (MAB represents a promising group of alternatives, where M stands for a transition metal, A typically denotes Al, and B is boron) phase system. First, the first-principles calculations were performed to reveal the unique crystal and layered structure of the MoAlB ceramics and to predict their potential for use as an EMW absorption material. Subsequently, a series of MoAlB ceramics were synthesized at temperatures ranging from 800 to 1300 °C, and the influence of temperature on the phase compositions and microstructures of the obtained MoAlB ceramics was characterized and analyzed. Finally, the practical EMW absorption performance of the prepared MoAlB ceramics was evaluated via a combination of experiments and radar cross-sectional calculations. The MoAlB sample synthesized at 900 °C exhibits superior EMW absorption performance, achieving an impressive minimum reflection loss (RL) of −50.33 dB. The unique layered structure and good electrical conductivity of the MoAlB samples are the main reasons for their enhanced wave absorption performance, which provides interfacial polarization and multiple dielectric loss mechanisms. Therefore, this study not only contributes to the understanding of the preparation of MoAlB materials but also provides potential guidance for their utilization in the realm of electromagnetic wave absorption.