Intelligent Off/On Switchable Microwave Absorption Performance of Reduced Graphene Oxide/VO2 Composite Aerogel

Abstract Intelligent microwave absorption (MA) materials possess the ability to dynamically change their microwave absorption performance, according to real‐time requirements, and it is of great significance in future civil and military fields. For the first time, the reduced graphene oxide/VO 2 composite aerogels are developed with off/on switchable MA performance, and the switchable mechanism is originated from the unique phase change behavior of VO 2 . As temperature increases (>68 °C), the VO 2 displays the phase change from monoclinic to rutile phase, which accompanies with significant changes in aerogel's electrical conductivity as well as its permittivity, and consequently leads to off/on switchable MA performance. Particularly, two different off/on switch modes, “on to off” and “off to on”, can be separately realized by different composite aerogels as temperature increases, and this off/on switchable MA performance is also confirmed with good cycling stability. More importantly, during the off/on switch process, the maximum changes for the effective absorption bands (ΔEAB) and RL values (ΔRL) can be as high as 7.27 GHz and 49 dB, which exceeds most current reports. Besides, the RCS simulations on aircrafts have been performed and verified this intelligent MA performance, thus providing useful guidance for next‐generation smart electromagnetic devices in various fields.