Preparation and microwave absorption property of micro-coiled carbon fibers

Micro-coiled carbon fibers were prepared by catalytic pyrolysis of acetylene with nanosized nickel powder catalyst using the substrate method. The morphology of micro-coiled carbon fibers was observed through field emission scanning electron microscopy. It was found that the fiber and coil diameter of the obtained micro-coiled carbon fibers is about 500-600nm and 4-5 mu m, respectively. Most of the micro-coiled carbon fibers obtained were regular double carbon coils, but a few irregular ones were also observed. Three samples that were prepared with micro-coiled carbon fibers, and they are different thickness. the microwave absorption property of the samples were test by microwave measure line system between 8.5GHz similar to 11GHz. To the sample that's thickness of carbon fibers is 8 similar to 10mm, the reflection coefficients can get -30dB. The result shows the micro-coiled carbon fibers have absorption effect obviously.