Ultralight, highly compressible and fire-retardant graphene aerogel with self-adjustable electromagnetic wave absorption
Ultralight, highly compressible and fire-retardant graphene aerogel with self-adjustable electromagnetic wave absorption
复制标题
具有自调节电磁波吸收的超轻、高度可压缩和阻燃的石墨烯气凝胶
DOI：
10.1016/j.carbon.2018.08.014
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发表时间：
2018-11-01
期刊：
影响因子：
10.9
通讯作者：
Liu, Xiaobo
中科院分区：
文献类型：
--
作者：
Wang, Zicheng;Wei, Renbo;Liu, Xiaobo
通过温和的原位自组装和热退火工艺成功制备了具有超轻密度和高压缩性的宏观三维（3D）自支撑多孔全石墨烯气凝胶。所形成的互连的3D多孔石墨烯网络、高热稳定的全石墨烯组合物和气凝胶的大孔隙率使得可以在燃烧期间快速移除热量，表现出显著的阻燃性。同时，高达75%的高应变水平下的良好可恢复压缩性赋予气凝胶在体积电导率方面具有高灵敏应变响应特性，从而为实现3D建筑内部自由空间和电导率的调节开辟了新途径。基于此结果，石墨烯气凝胶的微波吸收性能通过简单的机械压缩有效地自调节。当压缩应变率为30%时，在厚度为4.81 mm时，最佳吸波值可达61.09 dB，带宽为6.30 GHz。(C)2018爱思唯尔有限公司版权所有
Macroscopic three-dimensional (3D) free-standing porous all-graphene aerogel with ultralight density and high compressibility is successfully fabricated through a mild in-situ self-assembly and thermal annealing processes. The formed interconnected 3D porous graphene network, high thermal stable all-graphene composition and large porosity of aerogels made it possible to remove heat quickly during combustion, exhibiting a conspicuous fire-retardancy. Meanwhile, excellent recoverable compressibility with high strain levels of up to 75% endowed the aerogel with high sensitive strain-responsive characteristic in volume electrical conductivity, thereby opening a new way for realizing the adjustment of internal free space and electrical conductivity of 3D architecture. Based on the results, the microwave absorption performance of the graphene aerogel was effectively self-adjusted via a simple mechanical compression. The optimal absorbing value was up to 61.09 dB with a broad qualified bandwidth of 6.30 GHz at the thickness of 4.81 mm when the compression strain ratio of the sample was controlled to be 30%. (C) 2018 Elsevier Ltd. All rights reserved.