Highly photosensitive titanium dioxide and process for forming the same

Abstract

A highly photosensitivity titanium oxide composition includes a plurality of nanosize particles including titanium dioxide and titanium suboxide. The particles are substantially non-stoichiometric (TiO2-x, 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 10−6 cm3/g at 300 K, and are least 30% by weight rutile. A related method of forming a high photosensitivity titanium oxide composition includes the steps of providing a titanium chloride compound, such as titanium tetrachloride, an oxygen-containing gas and hydrogen, wherein a concentration of the hydrogen is in a stoichiometric excess (H2:O2) 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 burning 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.

Dependencies are inferred from the claim text.