Nano sulfur particles decorated bi-lamella composites for superior electromagnetic wave absorption

Sulfur nanoparticles decorated bi-lamella composites with multiple interfaces were constructed by introducing a handful of nano-S particles into the interlayer of graphene and poly (3,4-ethylene-dioxythiophene): poly (styrenesulfonate) (GSP). Graphene and PEDOT: PSS with large surface areas and abundant functional groups offer adequate contact sites for the chemical confinement of sulfur nanoparticles. Based on the equivalent circuit theory, insulating sulfur could commendably regulate hopping conduction by slowing down the hopping electrons among the layers. Meanwhile, the substantial conductivity differences result in evident interfacial polarization (MWS effect). With the favorable permittivity behavior and multiple interfacial polarizations, more microwaves could be brought into the interior of absorber and were consumed. The GSP-paraffin composites with 35 wt% GSP loading possess the minimum reflection loss (RL) value of -21.9 dB at 1.6 mm, and effective absorption bandwidth of 4.72 GHz. This work demonstrates the significant role of multi-interfaces on microwave absorption.