Effect of La@@u3+@ on evolution of TiO@@d2@ coating layers on lamellar sericite and their pigmentary properties

• Published in: Transactions of Nonferrous Metals Society of China Vol. 19; no. 3; pp. 626 - 634
• Main Authors: Ren, Min, Yin, Heng-Bo, Lu, Zhang-Zhun, Ge, Chen, Wang, Ai-Li, Yu, Long-Bao, Jiang, Ting-Shun
• Format: Journal Article
• Language: English
• Published: 01.06.2009
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(08)60324-6

TiO@@d2@-coated sericite powders were prepared by the chemical deposition method starting from lamellar sericite and TiCl@@d4@ in the presence of La@@u3+@. After calcination at 900 'C for 1 h, the resultant TiO@@d2@ nanoparticles on the sericite surfaces exist in anatase phase. The light scattering indexes of the TiO@@d2@-coated lamellar sericite powders are dozens of times higher than those of the naked lamellar sericite powders, varying with different contents of La@@u3+@. The presence of La@@u3+@ in the deposition solution is beneficial to the formation of the small-sized anatase TiO@@d2@ nanoparticles. The presence of La@@u3+@ also favors the formation of the dense and uniform island-like TiO@@d2@ coating layers in a large range of the mass ratio of TiO@@d2@ to sericite from 5% to 20%. XPS analysis shows that when La@@u3+@ is absent in the reaction solution, TiO@@d2@ coating layers anchor on the sericite surface via Ti - O - Si and Ti - O - Al bonds. The presence of La@@u3+@ causes the formation of Si - O - la and Al - O - la bonds on the sericite surface and Ti - O - la bond on the surface of TiO@@d2@ coating layers.