High-Quality Ultrathin Gd2O2S Nanosheets with Oxygen Vacancy-Decorated rGO for Enhanced Electromagnetic Wave Absorption

The development of extreme performance and multifunctional electromagnetic (EM) wave absorption materials is essential to eliminating undesirable frequency EM pollution. As a promising rare-earth compound, gadolinium oxysulfide (Gd2O2S) has become a significant field of study among nanomaterials with multidisciplinary applications. Herein, the ultrathin Gd2O2S nanosheets with 1 nm thickness were fabricated via a facile hot injection method and then mixed with reduced graphene oxide (rGO) through coassemble and carbonization methods to form Gd2O2S/rGO composites. As a new kind of multifunction EM-wave absorption materials, Gd2O2S/rGO composites exhibited excellent EM-wave absorption performance with an absorption capacity of -65 dB (2.1 mm) and an adequate absorption bandwidth of 5.6 GHz at 1.9 mm. Additionally, their EM-wave absorption mechanisms have been unveiled for the first time. The outstanding EM-wave absorption performance of Gd2O2S/rGO composites could be attributed to the ultrathin Gd2O2S nanosheets with oxygen vacancy and rGO layers with high conductivity and large specific surface area, which will also facilitate the polarization loss, conductivity loss, and multiple reflection and scattering of EM waves between the rGO layer and Gd2O2S nanosheets. Overall, compared to previously reported rGO-based EM-wave absorption materials, this work provides a promising approach for the exploitation and synthesis of Gd2O2S/rGO composites with lightweight and high-performance microwave attenuation.