A versatile N-doped honeycomb-like carbonaceous aerogels loaded with bimetallic sulfide and oxide for superior electromagnetic wave absorption and supercapacitor applications

Abstract

Electromagnetic pollution and electrochemical energy consumption have driven enormous endeavors in electromagnetic wave absorption materials and energy storage devices, however, designing versatile composites for addressing the issue remains a huge challenge. Herein, a versatile honeycomb-like N-doped carbon/bimetallic sulfide and oxide (N–CoFe2O4-CoxSy/FexSy@C) composites aerogel was designed via a simple mechanical mixing, freeze-drying and heat treatment method. As-prepared N–CoFe2O4-CoxSy/FexSy@C composites exhibited excellent electromagnetic wave absorption and electrochemical performances. The minimum RL can reach −51.9 dB at 15.5 GHz, with an effective frequency bandwidth (RL < −10 dB) of 4.01 GHz (13.73–17.74 GHz) at a thickness of 1.5 mm, these remarkable properties were originated from the abundance dipole/interfacial polarization along with multiple magnetic attenuation process. More importantly, an outstanding specific capacitance of 2883 F g−1 at 1 A g−1 and excellent cycling stability of 89.5% after 5000 cycles were also achieved, which is ascribed to the affluent active sites and well-defined hetero-architecture. Considering the novel N–CoFe2O4-CoxSy/FexSy@C composites aerogel possessing a unique blend of excellent electromagnetic wave absorber and supercapacitors electrodes, these multifunctional features would be highly promising for the next-generation environmental remediating materials.