A multiscale hierarchical architecture of a SiC whiskers–graphite nanosheets/polypyrrole ternary composite for enhanced electromagnetic wave absorption†
Abstract
A core–shell SiC whiskers–graphite nanosheets/polypyrrole (SiCw–GNs/PPy) heterostructure with excellent electromagnetic (EM) absorption performance was successfully prepared by a simple combined method using glucose as the carbon precursor. The content of GNs could be tailored by the mass fraction of glucose, while a substantial decrease of EM absorption performance of SiCw–GNs is achieved as the GN content increases, which could be attributed to the inferior impedance matching degree and small attenuation constant. Impressively, on coating with the conductive polymer PPy by a simple chemical polymerization method, the SiCw–GNs/PPy heterostructures exhibited superior EM absorption abilities with a minimum reflection loss (RLmin) value of −64.2 dB and a maximum effective bandwidth of 7.9 GHz, and the matched characteristic impedance and improved loss ability of the SiCw–GNs/PPy heterostructures account for the significant enhancement. The core–shell SiCw–GNs/PPy heterostructures in the present study could be considered as a promising candidate for the oncoming generation of microwave absorbing materials.