Preparation of nickel doped mesoporous carbon for enhanced microwave absorption performance

Abstract Herein, the polypyrrole coated and Nickel doped mesoporous carbon (MC) composites were synthesized by the Stober and in-situ polymerization methods. Firstly, the carbon mesoporous was derived from silica spheres by impregnated in a water-based solution containing melamine and formaldehyde. Secondly, the nickel doped mesoporous carbon was prepared into the 0.6 g of Ni(NO3)2·6H2O solution and denoted as NiMC. Finally, the core-shell structure composed of NiMC@polypyyrole was synthesized by in situ polymerizations (P@NiMC). The surface characterization results showed that the presence of Ni in mesoporous carbon increased the pore volume, BET surface area and pore size distribution ranges. The dielectric and magnetic properties of MC, NiMC and P@NiMC were measured for the electromagnetic wave absorption performance in the Ku-band. The P@NiMC exhibited better dielectric loss ability compared with MC and NiMC due to the polarization effects. The P@NiMC displayed better electromagnetic wave absorption with a minimum reflection loss of –13.42 dB at 12.4 GHz frequency. In addition, the effective absorption bandwidth (RL