LAUSR

Abstract Macro-assembled carbon-based films (GF) have demonstrated tremendous functional applications as high electrical/thermal conductors, and electromagnetic interference (EMI) shielding materials. Here, we report the synergistic effect of graphene and carbon nanotubes (CNT), that electrical conductivity significant improves from 1.78 × 105 to 2.74 × 105 S m−1, and thermal conductivity improves from 510 to 1154 W m−1 K−1 simply by adding 20 wt% CNTs into the graphene films. Moreover, the EMI shielding performance of the macro-assembled graphene-CNT composite films improves from ∼50 dB for pure GF to ∼60 dB for GF with 20 wt% CNT load. Our finding of the synergistic effect opens an avenue to design materials with higher electrical conductivity, thermal conductivity and EMI shielding performance.