Double salt-template strategy for the growth of N, S-codoped graphitic carbon nanoframes on the graphene toward high-performance electromagnetic wave absorption

The increasingly serious electromagnetic radiation urgently call for high performance electromagnetic wave (EMW) absorbers. Hollow carbon nanostructures are promising for lightweight EMW absorbers. However, due to lack of sufficient polarization centers, the EMW absorption property of hollow carbon nanosturctures is still unsatisfactory. Herein, we develop a double-salt template method for fabrication of N, S-codoped graphitic carbon nanoframes (GF) that anchored on the graphene sheets (GS). The GFs in the sample (N, S-GF/GS) have a width of about 51 nm and a wall thickness of only 4.8 nm. Furthermore, the graphene plane in the GF is perpendicular to the graphene plane in the GS, leading to the formation of numerous interfaces between the graphene planes perpendicular to each other. Theoretical calculations indicate that the interfaces can induce the interfacial polarization loss, and the N, S co-doping can cause dipole polarization loss, both of which enhance the EMW absorption performance of the N, S-GF/GS. The minimal reflection loss and efficient absorption width of the N, S-GF/GS at a low filler ratio of 10 wt% are -45.64 dB at the matching thickness of 2.3 mm and 4.35 GHz with the thickness of 1.5 mm, respectively, superior to most of carbon-based absorbers. Our proposed method opens a promising way for high-performance EMW absorbers.