Patent ID: 7731915

Claim:
Pollutant decomposition device comprising at least one outer transparent sheet and at least one inner transparent sheet being arranged such that a gap is formed between them and such that the gap is in communication with a surrounding gaseous composition on one side of the device such that the gaseous composition can pass through the gap, the device further comprising a photocatalyst arranged in the gap on the surface of the inner transparent sheet, the photocatalyst being in contact with the gaseous composition within the gap at a same surface as being irradiated through said outer transparent sheet, the irradiated surface of the photocatalyst being in contact with the gaseous composition within the gap, wherein the outer transparent sheet has a high degree of ultraviolet transmittance compared with the inner transparent sheet, wherein the ratio between the ultraviolet transmittance of the outer transparent sheet and the inner transparent sheet is in the ranged of 10:8 to 10:1.