Effect of graphene grains size on the microwave electromagnetic shielding effectiveness of graphene/polymer multilayers

Abstract

The influence of chemical vapor deposition (CVD) graphene grain size on the electromagnetic (EM) shielding performance of graphene/polymethyl methacrylate (PMMA) multilayers in Ka-band was studied both experimentally and theoretically. We found that increasing the average graphene grain size from 20 to 400 μm does not change the EM properties of heterostructures consisting of graphene layers sandwiched between submicron thick PMMA spacers. The independence of EM interference shielding effectiveness on the graphene grain size between 20 and 400 μm allows one to use cheaper (or more convenient regimes of CVD) graphene samples with low crystallinity and small grain size in the development of new graphene-based passive EM devices operated at high frequencies.