Preparation of nitrogen and sulfur co‐doped graphene/Fe 3 O 4 /C nanocomposite and study on the absorbing properties

Nitrogen and sulfur co-doped graphene oxide (NS-GO) is obtained using a simple hydrothermal method using thiourea as nitrogen source and sulfur source, and then nitrogen and sulfur co-doped graphene/Fe 3 O 4 (NS-rGO/Fe 3 O 4 ) composite is synthesized by a solvent method. On this basis, nitrogen and sulfur co-doped graphene/Fe 3 O 4 /C nanocomposite (NS-rGO/Fe 3 O 4 /C) is obtained using a solvent method combined with a high temperature calcination process using pitch as carbon source. When the matching thickness is 2.7 mm, the NS-rGO/Fe 3 O 4 /C has a reflection loss peak at 10.56 GHz, the value of which is − 46.33 dB, and the effective absorption (RL ≤ − 10 dB) bandwidth of the nanocomposite is 5.04 GHz. Compared with NS-rGO/Fe 3 O 4 , the NS-rGO/Fe 3 O 4 /C shows higher reflection loss (RL) value, thinner matching thickness and wider effective absorption (RL ≤ − 10 dB) bandwidth. The presence of amorphous carbon regulates the dielectric parameters of the material and increases the interface of the material. Sulfur and nitrogen diatoms regulate the band gap of graphene, and the composite material has good impedance matching characteristics and multiple interface effects.