Surface characteristics of hydrous silica-coated TiO particles
نویسندگان
چکیده
The surface characteristics of hydrous silica-coated TiO particles are experimentally studied. Different analytical techniques were 2 Ž . used to characterize the Si oxide coatings on TiO particles. The high-resolution transmission electron microscope HRTEM , z-potential 2 Ž . analyzer and X-ray photoelectron spectroscope XPS analyses show that hydrous silica is continuously coated on the surface of TiO2 particles. From the chemical shift of binding energy of O 1s and Ti2p on coated particles and FTIR analyses of absorption band, it is 3r2 inferred that Si oxide in the coating film is combined onto TiO particle surface through chemical bond of Ti–O–Si. The electrokinetic 2 behavior of TiO particles can be modified significantly by dense film coating. q 2002 Elsevier Science B.V. All rights reserved. 2
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