The entangled CNT anchoring in graphene using CVD approach for intelligent absorbing materials with thermal sensitivity effect

Abstract

Single-type carbon material is often limited in its application in the field of intelligent absorption due to their lack of outstanding performance. However, traditional physical mixing methods are difficult to achieve effective interface bonding and multifunctional coupling of carbon materials. Here, we developed an effective method to prepare the entangled CNTs anchoring in graphene for intelligent absorbing materials possessing thermal sensitivity effect combing hydrothermal and CVD methods. Interestingly, ultrafine CNTs with diameter below 18 nm catalyzed from Fe/Co nanocrystals well dispersed on rGO surfaces. The as-designed dielectric rGO-CNTs hybrids strongly bonding with magnetic Fe/Co catalyst have the excellent microwave absorption performance. The RL_min value of the −37.7 dB at thickness of 1.6 mm is obtained for rGO-CNTs, which is better than pure carbon materials. Furthermore, this rGO-CNTs microwave absorbing materials also possess thermal sensitivity effect. The linear fitted relationship of (R-R₀)/R₀ −temperature is found with the slope of 0.2 %/°C, showing the regular and steady trends. It indicates a highly thermal sensitive feature has great potential for intelligent absorbing materials. This study opens a novel pathway for ultrafine CNTs entangled with graphene enhancing its high-performance microwave absorption coupled with thermal sensitivity effect.