Intelligent Off/On Switchable Microwave Absorption Performance of Reduced Graphene Oxide/VO2 Composite Aerogel. (22nd July 2022)

• Record Type: Journal Article
• Authors: Cheng, Zheng; Wang, Ruofeng; Cao, Yishu; Cai, Zhihao; Zhang, Zhiwei; Huang, Yi
• Is Part Of: Advanced functional materials. Volume 32:Number 40(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-22
• Subjects: graphene aerogels -- microwave absorption -- phase‐change behavior -- VO 2; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202205160
• Languages: English
• ISSNs: 1616-301X

Abstract

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/VO2 composite aerogels are developed with off/on switchable MA performance, and the switchable mechanism is originated from the unique phase change behavior of VO2 . As temperature increases (>68 °C), the VO2 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. Abstract : The graphene/VO2 composite aerogel displays real‐time off/on switchable microwave absorption performance, which is induced by the phase change behavior of VO2 . The maximum changes for the effective absorption bands (ΔEAB) and RL values (ΔRL) can be as high as 7.27 GHz and 49 dB.