HIGHLY PHOTOSENSITIVE TITANIUM DIOXIDE AND PROCESS FOR FORMING THE SAME

摘要

A highly photosensitivity titanium oxide composition includes a plurality of nanosize particles including titanium dioxide and titanium suboxide. The particles are substantially non-stoichiometric (TiO<SUB>2-x</SUB>, wherein 0.1< x< 0.3 at a surface of the particles, and in the bulk of the particles x is less than at the surface), provide a magnetic susceptibility value (X) of at least 0.8 10<SUP>-6</SUP> cm<SUP>3</SUP>/g at 300 K, and are least 30% by weight rutile. A related method of form- ing a high photosensitivity titanium oxide composition includes the steps of providing a titanium chloride compound, such as titanium tetrachloride, an oxygen-containing gas and hy- drogen, wherein a concentration of the hydrogen is in a stoichiometric excess (H<SUB>2</SUB>:O<SUB>2</SUB>) from 2.02: 1 to 2.61 : 1. The titanium chloride compound is burned in the presence of oxygen from the oxygen-containing gas and hydrogen to form plurality of ultrafine particles comprising titanium dioxide and titanium suboxide. The method can include the steps prior to the burn- ing step of mixing the titanium chloride compound, oxygen and hydrogen and heating the same to 50 to 100 °C, such as from 70-100 °C.