Hybridization-induced Polarization of Graphene Sheets by Intercalation-polymerized Polyaniline towards High Performance of Microwave Absorption.

An intercalation polymerization is applied to regulate the hybridizing structures of polyaniline@graphene (PANI@GE). Polarization of graphene sheets is realized, which is attributed to the hybridization by the in situ intercalation-polymerized polyaniline molecules. The polarizing effect on graphene is confirmed by characterizations and DFT calculations, and the results indicate that it exists distinct p-π and π-π interactions between the PANI molecules and the graphene sheets. As a result, this new structural hybrid leads to a high performance of microwave absorption. The minimum reflection loss (RL) of the optimized PANI@GE hybrid can be as low as -64.3 dB at 10.1 GHz with the RL bandwidth of -10 dB being 5.1 GHz (from 8.6 to 13.7 GHz). Further study reveals a special mechanism for the electromagnetic energy consumptions by the structural resonance of the polarized graphene-based hybrids, a complex macromolecule. In addition, the fully separated GE provides a good impedance matching, together with the widely-held multi-scaled relaxations of the interfacial polarization.