Preparation and microwave absorbing properties of nickel/carbon derived from kapok fiber composites
Recently,biomass carbon has been widely used in the field of microwave absorption due to its low cost,easy preparation,excellent physical and chemical properties,and porous structure.However,its micro-wave absorption performance is still limited by poor impedance caused by high conductivity.Here,nickel(Ni)is used to modify kapok fibers,and then the nickel/carbon derived form kapok fiber(Ni/C)composites are ob-tained at different carbonization temperatures.The scanning electron microscopy results indicate that the size of Ni particles increases,and more defect structures appear on the surface of kapok fibers with the increase of car-bonization temperature.The XRD and XPS results confirmed the successful combination of Ni and carbon de-rived from kapok fiber.The Raman results indicate that the increase in carbonization temperature results in more graphite structures,enriching the conductive loss ability of the composites.Finally,we mixed the com-posite with paraffin at an ultra-low filling ratio of 5∶95,and the Ni/C-800 showed a reflection loss value of-52.6 dB and an effective absorption bandwidth of 8.32 GHz.The excellent absorption performance of composites depends on the synergistic effect of attenuation ability and impedance matching,the combined effect of dielectric and magnetic losses,and the enhancement of multiple scattering ability caused by large specific surface area and hollow porous structure.
kapok fiberbiomass carbonnickelultra-low fillinghollow and porous
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维普
