Absorption-enhanced EMI shielding using silver decorated three-dimensional porous architected reduced graphene oxide in polybenzoxazine composites

The proliferation of wearable and portable electronic media has increased the demand for highly efficient materials that can be used to create shields against electromagnetic interference. Herein, we report the development of such shielding materials using silver nanoparticles and porous graphene. The silver nanoparticle-decorated porous architecture on reduced graphene oxide nanosheets in polybenzoxazine thermoset polymers was fabricated through chemical synthesis. The three-dimensional interconnected porous structure with metal silver nanoparticles exhibited satisfactory conductivity and delocalization of charge attributes, which enhanced the electromagnetic interference shielding efficiency in the composites. The effective combination of silver nanoparticles with the three-dimensional porous architecture of reduced graphene oxide in polybenzoxazine resulted in multi-reflections and current-induced magnetic dipoles. This enhanced the absorption and resulted in a high electromagnetic interference shielding efficiency of 54 dB for a thickness of 0.65 mm in the X-band frequency region.