Abstract: An air purifying system includes one or more air permeable photocatalytic elements defining a core cavity having a sealed top end and an open bottom end. A sealed air flow path ensures that air travels from an outside of the core cavity, through the one or more photocatalytic elements, into the core cavity, to be expelled through the open bottom end. A UV radiation source disposed within the core cavity irradiates air travelling along the sealed flow path and an interior of the one or more photocatalytic elements. Each photocatalytic element is manufactured using a substrate, that is conductive of and transparent to UV radiation, coated with a photocatalyst. A non-photocatalytically active material is initially coated on the substrate and is then converted to a photocatalyst by calcination.

Abstract: An air purifying system includes one or more air permeable photocatalytic elements defining a core cavity having a sealed top end and an open bottom end. A sealed air flow path ensures that air travels from an outside of the core cavity, through the one or more photocatalytic elements, into the core cavity, to be expelled through the open bottom end. A UV radiation source disposed within the core cavity irradiates air travelling along the sealed flow path and an interior of the one or more photocatalytic elements. Each photocatalytic element is manufactured using a substrate, that is conductive of and transparent to UV radiation, coated with a photocatalyst. A non-photocatalytically active material is initially coated on the substrate and is then converted to a photocatalyst by calcination.

Abstract: The invention provides a water purification system and method for combining ultraviolet germicidal irradiation and photocatalysis in a helical reactor geometry that maximizes both the photocatalytic efficiency and the germicidal dosage of the ultraviolet irradiation in deactivation of microbes and the destruction of contaminant organic compounds.

Abstract: The invention provides an air purification system and method for combining filtration, ultraviolet irradiation, and photocatalysis, in an annular geometry that maximizes the photocatalytic efficiency of the ultraviolet light in the deactivation of microbes and the photocatalysis of volatile compounds.