Electrorheological response behavior of H2Ti2O5@MoS2@SiO2 core-shell nanoparticles

Abstract

In this paper, a novel H2Ti2O5@MoS2@SiO2 ternary composite material was prepared by a combination of dual hydrothermal method and controlled hydrolysis method, in which H2Ti2O5 nanotubes are tightly combined with hierarchical molybdenum disulfide, and the unique structure of titanate nano whiskers, including the loosely bound alkali metal ions between the titanate layers with high dielectric constant and the large aspect ratio, which induce active response to the electric field. Flower-like molybdenum disulfide provides electrical conductivity, and silicon dioxide as a insulative coating layer can suppress excessive the electrical conductivity of the two-dimensional material. The morphological evolution was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results of showed that the sheet-shaped molybdenum disulfide coated with curved H2Ti2O5 nanotubes showed a honeycomb structure with uniform size. Silicon oxide acts as a cladding layer to increase the thickness of the flakes. The existence of H2Ti2O5, molybdenum disulfide and silicon dioxide is confirmed by X-ray powder diffractometer (XRD) and Fourier transform infrared spectroscopy (FT-IR). The prepared product was confirmed by XPS, BET test and electrorheological rheometer. Core/shell nanoparticles not only exert the active response characteristics of titanate nanoparticles and molybdenum disulfide to electric field, but also inherit the excellent characteristics of a core-shell structure produced by the interface polarization and the synergistic effect of the polar groups on the surface of the two-dimensional material further enhance the electrorheological effect.