High-performance electromagnetic wave absorption in carbon nanotubes/reduced graphene oxide composites with graphene oxide-engineered porous architectures

Abstract

The escalating electromagnetic pollution from electronic devices necessitates high-performance microwave absorbers. Herein, we fabricate lightweight carbon nanotube (CNT)/reduced graphene oxide (rGO) porous composites via graphene oxide (GO)-mediated reconstruction of melamine-derived microspheres. Multiple characterizations (SEM, XRD, Raman, and Brunauer–Emmett–Teller) confirm that rGO can manipulate disordered CNT aggregates into interconnected 3D scaffolds with regular nanopores and enhance graphitic ordering. Electromagnetic analysis (2–18 GHz) indicates that incorporating rGO increases the dielectric loss tangent and facilitates optimal impedance matching. Consequently, the CNT/rGO-composite exhibits exceptional absorption capabilities: −40 dB reflection loss at 8 GHz (3.0 mm thickness) and a 4 GHz effective bandwidth (RL ≤ −10 dB) at 2 mm. Radar cross section simulations further demonstrate that the composite contained rGO with a maximum attenuation of 21.2 dBsm at 8 GHz, validating radar stealth performance. Such a high electromagnetic wave absorption performance is attributed to the synergetic effects of long-range propagation paths from internal multiple reflections, additional polarization centers due to heterogeneous interfaces, and other effects. Experimental and simulation results provide insights into the composite manufacturing of one-dimensional carbon nanotubes and two-dimensional reduced graphene oxide.