Regulation of Sulfur doping on rational synthesized porous hollow carbon spheres and their superior electromagnetic wave attenuation performance

Recently, developing an ideal electromagnetic wave (EM) absorption material, which can simultaneously possess the good abilities of EM energy dissipation, chemical stability and lightweight, has attracted significant attention. Herein, rational designed porous hollow carbon spheres have been prepared via a controllable chemical etching process and followed by a regulated sulfur doping process in the carbon frameworks. The content of sulfur doping can be exactly tuned by simplify adjusting the amount of thioacetamide during the reaction in which can effectively achieve the good balance between the impedance matching and dielectric loss. Benefiting from the porous hollow structure, good impedance matching condition and high dielectric loss, the as-prepared sulfur-doped porous hollow spheres (HCSs) could obtain an efficiency EM attenuation performance, with a maximum effective absorption bandwidth (ƒE) of 6.7 GHz at an absorbent thickness of 2.0 mm. When the matching thickness was only 1.65 mm, the minimum reflection loss (RL) value reached − 53 dB. Therefore, this work confirms that the sulfur-doped porous hollow carbon spheres are expected to be reliable microwave attenuation materials, which also opens up a potential strategy for design and synthesis of high-performance carbon-based materials with tunable EM properties.