期刊
CHEMICAL ENGINEERING JOURNAL
卷 368, 期 -, 页码 285-298出版社
ELSEVIER SCIENCE SA
DOI: 10.1016/j.cej.2019.02.193
关键词
N-doped graphene foams; Open reticular structures; Interconnected conductive network; Electromagnetic wave absorption
资金
- National Natural Science Foundation of China [51602259]
Chemical doping of graphene with heteroatoms is expected to be a promising strategy to enhance the electromagnetic wave attenuation capability, however, the intrinsic mechanism is not investigated in-depth. In this manuscript, ultra-lightweight N-doped graphene foams (rho = 10.5-16.6 mg/cm(3)) with high porosity and open reticular structures are prepared via a self-assembled hydrothermal reaction and a freeze-drying process. Compared with pure graphene foams, the presence of N heteroatoms helps to build open reticular walls and tailors the electrical properties, leading to strong electromagnetic wave absorption capacity and broad absorption bandwidth simultaneously, and meanwhile, the investigation of N bonding configurations illustrates that the presence of pyrrolic/pyridinic N are mainly essential for the dipolar relaxation loss whereas graphitic N is beneficial to the conduction loss. When the bulk density is 11.6 mg/cm(3), the maximum reflection loss of the absorber is -53.9 dB at 3.5 mm with a low filler loading of only 5 wt%, and the absorption bandwidth exceeding -10 dB is 4.56 GHz with a thickness of 2 mm, the highly efficient electromagnetic wave absorption performance strongly originates from the enhanced dipolar/interfacial polarizations, the multiple scatterings, the microscale circular conductive structures as well as the balanced impedance match. Furthermore, this monocomponent absorber can be an optimal candidate for ultra-lightweight and high-efficiency electromagnetic wave absorber without decorating other nanomaterials.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据