Doping Strategy To Boost the Electromagnetic Wave Attenuation Ability of Hollow Carbon Spheres at Elevated Temperatures

Abstract

Currently, the electromagnetic (EM) wave absorbers usually suffer severe performance degradation when they work for a while due to the generated heat issue. Developing a high-performance EM absorber with flexibility and adjustability that can effectively absorb the EM energy and convert into thermal energy at elevated temperature is highly desired but still remains a significant challenge. Herein, we demonstrate S-doped hollow carbon nanospheres used as fillers to fabricate a flexible and controllable EM absorber toward this challenge. Owing to the insertion of S-based polar groups in the graphitization area of carbon spheres, this EM absorber exhibits outstanding electromagnetic wave absorption capability with elimination of X-band EM wave performance at a temperature range of 298−423 K. Almost 90% of the Xband EM wave can be dissipated at 373 K, while the effective absorption rate of 75% can still be achieved at 423 K.

Dielectric Loss Mechanism in Electromagnetic Wave Absorbing Materials

“…Apart from N‐doped materials, S‐doping strategy is also effective to improve defect‐induced polarization. [ 125 , 126 ] In spite of the advance of single element doping, the influence of multiple elements co‐doping on EM wave absorption is also widely investigated. [ 127 , 128 , 129 , 130 ] Sun et al.…”

“…Apart from N-doped materials, S-doping strategy is also effective to improve defect-induced polarization. [125,126] In spite of the advance of single element doping, the influence of multiple elements co-doping on EM wave absorption is also widely investigated. [127][128][129][130] Sun et al fabricated N, S co-doped reduced graphene oxide (NS-rGO) and S, B co-doped rGO (SB-rGO) as EM wave absorbers.…”

Green Approach to Conductive PEDOT:PSS Decorating Magnetic-Graphene to Recover Conductivity for Highly Efficient Absorption

“…In the era of electronic information technology, electromagnetic radiation has harmful effects on the functions of precision electronic equipment and human health. Hence, preventing electromagnetic radiation has become a critical issue all over the world. − An effective approach is to develop efficient MA materials to counteract the increasing electromagnetic radiation. − Among the existing MA materials, graphene is one of the brightest stars. − Chen et al first reported graphene/epoxy composites and their EMI shielding performance, which attracted the attention of researchers. − Singh et al synthesized graphene oxide (rGO) with a layered and porous structure by thermal exfoliation of graphite oxide, which presented a high MA property . Cheng’s group explored lightweight and flexible 3D graphene foam composites, showing stable EMI shielding performance under repeated bending .…”

Research Progress of Metal Organic Frameworks/Carbon‐Based Composites for Microwave Absorption

“…In addition, the microstructure of carbon materials also plays an important role in the consumption of incident electromagnetic waves. [60][61][62][63][64] Therefore, an appropriate design on the microstructure of carbon materials is an important method to further improve material's microwave absorption performance, especially for carbon-based materials. [65,66] To date, some carbonbased materials with hollow, porous, sandwich-like, core-shell, and 3D microstructures have been proved to have excellent microwave absorption properties as expected.…”