Titanium oxide photocatalyst and method for producing the same

A method for producing a titanium oxide photocatalyst containing at least an anatase-type titanium oxide and fluorine, the method comprising the steps of:

• adjusting a pH of an aqueous dispersion solution of a titanium oxide with an alkaline solution until the pH thereof becomes in a range of 7.5 to 9.5, and thereafter filtering the solution;
• re-dispersing a filtration residue obtained by the filtration into water;
• obtaining a suspension by adding a fluorine compound to the re-dispersion solution obtained by the re-dispersion, and thereafter adjusting a pH of the suspension with an acid until the pH thereof becomes 3 or less, whereby the titanium oxide and the fluorine compound are caused to react with each other;
• and
• washing a reaction product obtained by the reaction, whereby a titanium oxide photocatalyst is obtained that contains at least the anatase-type titanium oxide and the fluorine, wherein a content of the fluorine is 2.5 wt % to 3.5 wt %, and, of an entirety of the fluorine, a proportion of the fluorine chemically bonded to the anatase-type titanium oxide is 90 wt % or more.