Preparation of TiO2–MWCNT core/shell heterostructures containing a single MWCNT and their electromagnetic properties

Abstract

TiO2–MWCNT core/shell heterostructures containing a single MWCNT have been successfully prepared via solvothermal method. TiO2–MWCNT heterostructures with different morphologies and electromagnetic (EM) properties have obtained by adjusting the weight ratio of titanium dioxide (TiO2) and multi-walled carbon nanotubes (MWCNT) (weight ratio: 1:1, 5:1 and 10:1). EDS spectrum and X-ray diffraction analysis reveal that the product is composed of Ti, O, and C elements, and the crystal structure of TiO2 is tetragonal anatase phase. SEM and TEM images show that the MWCNTs are coated by a thin layer of TiO2 crystals, and the average diameters of the needle-like TiO2 nanocrystals are less than 100 nm. EM properties of the as-prepared TiO2–MWCNT heterostructures are investigated in the 0.5–18.0 GHz range. The permittivity and permeability of the TiO2–MWCNT heterostructures change obviously as the weight ratio of TiO2 and MWCNT increases. Moreover, the typical resonance–antiresonance phenomenon can be observed in the permittivity and permeability curves.