Graphene sheets/polyaniline composite for electromagnetic interference shielding

The electromagnetic interference(EMI) shielding effectiveness(SE) of the graphene sheets/polyaniline(GSs/PANI) composite in different contents of GSs was investigated.The high crystalline GSs were prepared by DC arc-discharge method.The GSs/PANI composites were synthesized by an alcohol-assisted dispersion and pressing process.Compared with the pure PANI materials' Raman spectra,the GSs/PANI composites show the decrease of the characteristic peak intensity or a red shift of the peak,which is induced by the interaction between the GSs and PANI.The electrical conductivity of GSs/PANI composite increases with the increase of the GSs doping quantity and reaches to 19.4 S/cm at the mass fraction of 25%,which almost equals to that of pure GSs(20.1 S/cm).The EMI SE increases with the frequency and the GSs doping quantity.When the mass fraction of GSs is 25%,the EMI SE increases about 42%,from 19.8 dB to 34.2 dB in the range of 2-18 GHz.Besides,the absorption proportion increases from 66% to 81%,which indicates that the GSs/PANI composite is the absorption-dominated EMI shielding material.These also prove that GSs are excellent filler of the PANI because of their special structure and properties.There will be a wide application prospects in the field of EMI shielding and microwave absorption.