Preparation and enhanced electro-responsive characteristic of graphene/layered double-hydroxide composite dielectric nanoplates

To combine the advantages of a conducting graphene nanosheet (GNS) and insulating layered inorganic, we used a simple one-pot hydrothermal method to prepare two-dimensional dielectric nanoplates composed of a GNS/Mg-Al layered double-hydroxide (GNS/LDH) composite for use as a novel anisotropic electro-responsive electrorheological (ER) material. The structures of the samples were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, and scanning electron microscopy. The conductivity and dielectric properties were measured by an impedance analyzer, and the electro-responsive ER characteristic of the GNS/LDH composite dispersed in insulating oil was characterized by a rheometer. The results demonstrate that the LDH can provide an electrically insulating effect for GNS, while the incorporation of the conducting GNS can enhance the dielectric polarization of LDH. The GNS/LDH composite shows a significantly stronger ER effect compared to the pure LDH, especially under AC electric fields due to the enhanced polarization response.