▎ 摘　　要

NOVELTY - The device has base material whose surface is formed with photocatalyst (2) and water collecting and releasing material (3) i.e. moisture-absorbing photo-thermal organic gel. A light source device is arranged on a side of a filter screen (1). The light source device is provided with an UV light source and a visible light source. The light source device irradiates the photocatalyst and the water collecting and releasing material. Graphene (4) is arranged on a substrate and connected with the photocatalyst. USE - Photocatalyst purifying device for use in an air purifier (claimed). ADVANTAGE - The substrate is arranged with the photocatalyst and the water collecting and releasing material for generating a high oxidizing substance by the photocatalyst under irradiation of the light source device. The light source device irradiates generated light for releasing water by the water collecting and releasing material. The device can utilize water vapor as a carrier of the strong oxidizing substance when the water vapor is radiated for increasing diffusion rate of the water vapor to increase a purifying area of the strong oxidizing substance. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) an air purifier; and (2) an air purifying method. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a photocatalyst purifying device for use in air purifier. Filter screen (1) Photocatalyst (2) Water collecting and releasing material (3) Graphene (4)