Sedimentation of Barium Titanate Nanoparticles in a Suspension under Application of an Electric Field

Barium titanate nanoparticle (BT-NP) suspensions were prepared by dispersing sol-gel-derived BT-NPs in ethylene glycol monomethyl ether (EGMME) under sonication. When an electric field was applied, a part of the BT-NPs in a suspension was deposited on the cathode by electrophoretically deposition and most of the rest of the BT-NPs settled down towards the bottom of a container. The concentration of BT-NPs in the lower part of the container (Cbottom) increased with time until the Cbottom reached a specific concentration (threshold concentration) at which sedimentation of BT-NPs start to occur. The threshold concentration of the nanoparticles sedimentation gave a significant influence upon the aspect of a BT-NPs deposit formed on the cathode.