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• Porous carbon nanofibers were prepared by one-step method with ZnCl 2. • The structures of the porous carbon nanofibers were investigated systematically. • PCF-5 presented excellent MA due to the dielectric loss and multiple reflections. In this research, 1D porous carbon nanofibers (PCFs) were prepared by electrospinning and annealing process. The PCFs with excellent microwave absorption (MA) performance were prepared by a simple one-route method by mixing with different amount of ZnCl 2 in the precursors. During the process of annealing, ZnCl 2 can promote the formation of porous structures and ZnO or Zn complexes by gasifying at high temperature. The porous structures can enhance the multiple reflections and the ZnO or Zn complexes can enhance the dielectric loss. The obtained PCFs were characterized by SEM, TEM, XRD, Raman and XPS. The PCFs with 5 wt% ZnCl 2 exhibit excellent microwave absorption properties with a minimum reflection loss (RL min) of −51 dB at 9.1 GHz and the effective band under −10 dB ranges from 8 to 11 GHz with a width of 3 mm. It is believed that this method would be a facile approach for preparing porous carbon fibers as lightweight microwave absorption materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Egg white-derived HPC coupled with Fe 3 O 4 nanoparticles was fabricated. • Fe 3 O 4 /HPC displays a RL min of −57.8 dB at 7.36 GHz with a thickness of 3.48 mm. • Fe 3 O 4 /HPC possesses a broad effective absorption bandwidth of 6 GHz at 2.03 mm. Herein, Fe 3 O 4 nanoparticles encapsulated in hierarchical porous carbon (HPC) with outstanding microwave absorption performance was successfully synthesized by a facile strategy. Compared with the HPC frame, Fe 3 O 4 /HPC composite exhibits a significant improvement in microwave absorbing performance, in which the reflection loss value is up to −57.8 dB at 7.36 GHz with a thickness of 3.48 mm and a filling content of 40%, and the effective absorption bandwidth reaches 6 GHz covering the frequency range of 11.92–17.92 GHz. The above-mentioned outstanding properties can be ascribed to the porous architecture, the high specific area, and the complementary effect between Fe 3 O 4 nanoparticles and HPC. [ABSTRACT FROM AUTHOR]

• Electrospun carbon nanofibrous (ECNF) membranes were investigated for oil absorption. • Results from ECNF membranes with porous and/or hollow individual fibers were compared. • Hollow ECNF structure did not play a favorable role in capacity of oil absorption. • The result is ascribed to nanostructures generated from co-axial electrospinning. • The findings provide insights to develop absorbent material for oil spills. Current commercial oil absorbents such as polypropylene based materials are lack of exciting absorption capability for oil spill cleanup. Designing economic, efficient and stable absorbent for oil spill is still a challenge. Herein three types of carbon nanofibrous membranes with porous and/or hollow individual carbon nanofibers from bicomponent and co-axial electrospinning were prepared and their morphology, porosity, surface property as well as oil absorption capacity and reusability were characterized and compared. The results indicated that the hollow structure from co-axial electrospinning does not play a favorable role in oil absorption. The reasons may be attributed to surface nature, pore volume and nanometer scale interconnected hollow channel/pore structure that are naturally associated with co-axial electrospinning. [ABSTRACT FROM AUTHOR]