Redispersible rutile TiO2 nanocrystals in organic media by surface chemical modification with an inorganic barium hydroxide

The present paper describes the synthesis of the redispersible rutile TiO2 nanocrystals in organic media by surface chemical modification reaction in an aqueous barium hydroxide solution. In our facile surface modification reactions, the surfaces of the TiO2 nanocrystals are coated by bimetallic Ti-O-Ba spices and saturated with Ba-OH terminal groups. The inherent characteristics Such as morphology, size, crystallinity, and color of the nanocrystals remained almost unchanged after surface-treatment, but their dispersibility in organic media such as methanol and DMF were remarkably enhanced It is ascribed that Ba-OH groups in the surface of the TiO2 nanocrystals prevented the formation of covalently bound agglomerates through Ti-C-Ti condensation reaction among the nanocrystals during the Purification and water-elimination procedures. (c) 2005 Elsevier Inc. All rights reserved.