Effect of polyethylenimine on the dispersion and electrophoretic deposition of nano-sized titania aqueous suspensions

The dispersion and electrophoretic deposition (EPD) behavior of an aqueous suspension of nano-sized titania particles stabilized with a dispersant of polyethylenimine (PEI) were systematically investigated. The adsorption behavior of PEI on the titania surfaces indicated a high affinity adsorption of PEI at a high pH value while a low affinity adsorption was observed at a low pH value, which is consistent with the viscosity behavior of the suspension. The influences of the suspension pH, the added amount of PEI and the salt addition on the electrophoretic deposition behavior of the suspensions were studied.