PHOTOCATALYST, ITS MANUFACTURING METHOD AND LOW-TEMPERATURE OXIDIZING METHOD

PROBLEM TO BE SOLVED: To provide a photocatalyst capable of responding visible light over a long period without addition of fresh additives. SOLUTION: The first and second catalyst layer 3 and 4 are laminated in order on a substrate 2. The first catalyst layer 3 is composed of TiO2-x(wherein x is larger than 0 and smaller than 0.02) in an oxygen-defective state and has an inclined composition structure in which the oxygen defectiveness of TiO2-xis higher on the side separated from the second catalyst layer 4 toward the substrate than on the side of the second catalyst layer 4. The second catalyst layer 4 is composed of TiO2. The arrangement enables the photocatalyst to respond visible light, together with UV rays, in the first catalyst layer 3 without inclusion, e.g. ion injection, and also enables the second catalyst layer 4 to perform a photocatalyst reaction on the basis of UV rays, prevent invasion of external oxygen and control oxidization of the first catalyst layer 3 (TiO2-x). COPYRIGHT: (C)2007,JPO&INPIT