Pseudo‐binary composite of Sr ₂ TiMoO ₆ –Al ₂ O ₃ as a novel microwave absorbing material

Abstract In this work, a novel microwave absorbing material (MAM) made of a pseudo‐binary of Sr 2 TiMoO 6 –Al 2 O 3 (STM) is proposed first. The MAMs labeled as STM X ( X = 60, 70, 80 and 100, respectively), in which X is the initial weight percent of Sr 2 TiMoO 6 , were synthesized using the solid‐state reaction method. Compared with STM100, some equilibrium phases, including SrTiO 3 , Mo, Sr 8 (Al 12 O 24 )(MoO 4 ) 2 and a few undefined ones, are presented in the composites as evidenced by X‐ray diffraction results and scanning electron microscopy due to the chemical reaction between Sr 2 TiMoO 6 and Al 2 O 3 component. Besides conductance loss, heterogeneous interfaces between various equilibrium phases introduce interfacial polarization, which causes an enhancement of dissipation for the incident electromagnetic wave. Among the synthesized samples, STM80 presents the best microwave absorbing properties. It has a minimum reflection loss (RL min ) of − 26 dB and an effective absorbing bandwidth up to 2.7 GHz when the thickness is only 1 mm. This indicates that STM80 is a new type of microwave absorbing material with strong absorption and ultrathin thickness.