Lead sulfide/sulfur and nitrogen co-doped graphene quantum dots: Preparation, Characterization, and Microwave Absorbing properties

To prevent serious electromagnetic interference, a single-layer wave-absorbing coating employing lead sulfide/sulfur and nitrogen co-doped graphene quantum dots (PbS/S,N-GQDs) with epoxy resin as matrix was prepared. For this purpose, PbS/S,N-GQDs nanocomposites were prepared via simple and novel procedure. The prepared products were characterized through X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR) analysis. Results showed that S,N-GQDs have been distributed on the flower-like morphology of PbS in PbS/S,N-GQDs nanocomposites. The electromagnetic parameters of products were measured in the frequency range of ۸-۱۲ GHz by transmission/reflection technology, and electromagnetic loss mechanisms of the two particles were discussed, respectively. The microwave absorption properties of the coatings were investigated by measuring reflection loss (RL) using arch method. It was found that the ۱۰% of PbS/S, N-GQDs and ۵ mm thickness are the optimum condition for high RL efficiency. At this condition, maximum absorption and average absorption was measured -۱۶.۳ and -۴.۰۵ dB respectively.

کلیدواژه ها:

Microwave ، Electromagnetic interference shielding ، Nanocomposites ، Graphene quantum dot