Dispersion characteristics of α-Fe2O3 nanopowders coated with titanium dioxide by atomic layer deposition

Abstract

A TiO2 nanofilm was deposited on α-Fe2O3 nanopowders using the atomic layer deposition method. The TiO2 film was prepared at 300°C using Ti(N(CH3)2)4 and H2O as the precursor and reactant gas, respectively. The thickness and composition of the TiO2 surface were characterized by TEM and EDS measurements. The TEM results showed that the growth rate of the film was about 0.12 Å/cycle. The EDS and SAED analyses showed the presence of titanium oxide on the surface of the α-Fe2O3 nanopowders, confirming the deposition of the TiO2 nanofilm. The Zeta potential and sedimentation test results showed that the dispersibility of the coated nanopowders was higher than that of the uncoated nanopowders. This is attributed to the electrostatic repulsion between the TiO2-coated layers on the surface of the α-Fe2O3 nanopowders. The results revealed that the TiO2-coated layers modified the surface characteristics of the α-Fe2O3 nanopowders and improved their dispersibility.