The microstructure and electromagnetic interference shielding effectiveness of C/C composite surfaces modified by SiC nanoribbons@vertically oriented graphene

To ensure the performance of C/C composites, a surface-modified C/C composite was prepared with a C/C composite as the substrate, one-dimensional SiC as the intermediate, and vertically oriented graphene as the modification material without changing the microstructure or composition of the C/C composites. C/C composite surface modifications were prepared in two steps. Its specific surface area is improved from 0.25 m2/g to 10.44 m2/g, and the electromagnetic interference shielding efficiency is enhanced from 13.08 dB to 23.86 dB. Different from the C/C composites without surface modification, the electromagnetic interference shielding mechanism of surface-modified C/C composites changed from electromagnetic reflection to the interaction of electromagnetic absorption and reflection. The reason is that the increased specific surface area elongates the transmission paths of the electromagnetic waves by multiple reflections, leading to significantly improved electromagnetic interference shielding efficiency.