Hydrothermal synthesis of micro-flower like morphology aluminum-doped MoS2/rGO nanohybrids for high efficient electromagnetic wave shielding materials

In this study, a three-dimensional (3D) micro-flower like morphology aluminum-doped molybdenum disulfide/ reduced graphene oxide (Al@MoS2/rGO) nanohybrids have been developed using a simple and sensitive hydrothermal approach. Their electromagnetic (EM) parameters (permittivity, permeability) and microwave shielding parameters (S-11, S-12) have been analyzed and reported for the first time in the microwave frequency range of 8.0-12.0 GHz. It is interesting to note that the electrical conductivity of the nanohybrids increases with the doping concentration of Al-ions, whereas skin-depth has a reverse trend. The 12% Al@MoS2/rGO nanohybrid shows a higher total electromagnetic interference shielding effectiveness (EMI SE) value about SET-33.38 dB, whereas undoped MoS2/rGO nanohybrid exhibits a lower value around-17.07 dB at the same thin thickness. The higher doping concentration of Al-ion creates lattice distortion and crystal defects with high charge carrier mobility between multiple interfaces and at defective sites. Hence, the Al-doping into MoS2 lattice supported on the rGO surface can greatly enhance EM wave absorption and EMI SE value. The present work suggests that the 12% Al@MoS2/rGO nanohybrid can be treated as a good microwave absorbing and shielding material and useful in various techno-commercial devices.