Abstract: Titania having high visible light photocatalytic activity is prepared by (a) mixing titania with carbon powder; (b) heating the titania/carbon powder mixture to at least about 1000° C. in an inert or weakly reactive atmosphere; and (c) thereafter heating the resultant powder mixture to a temperature in the range of about 350 to about 1000° C. in an oxidizing atmosphere. The resultant titania may be used for detoxifying or disinfecting liquids for gases, for generating hydrogen from aqueous media and in sunscreens and sunglasses.

Abstract: Titania is a semiconductor and photocatalyst that is also chemically inert. With its bandgap of 3.2 and greater, to activate the photocatalytic property of titania requires light of about 390 nm wavelength, which is in the ultra-violet, where sunlight is very low in intensity. A method and devices are disclosed wherein stress is induced and managed in a thin film of titania in order to shift and lower the bandgap energy into the longer wavelengths that are more abundant in sunlight. Applications of this stress-induced bandgap-shifted titania photocatalytic surface include photoelectrolysis for production of hydrogen gas from water, photovoltaics for production of electricity, and photocatalysis for detoxification and disinfection.

Abstract: Titania having high visible light photocatalytic activity is prepared by (a) mixing titania with carbon powder; (b) heating the titania/carbon powder mixture to at least about 1000° C. in an inert or weakly reactive atmosphere; and (c) thereafter heating the resultant powder mixture to a temperature in the range of about 350 to about 1000° C. in an oxidizing atmosphere. The resultant titania may be used for detoxifying or disinfecting liquids for gases, for generating hydrogen from aqueous media and in sunscreens and sunglasses.

Abstract: Titania is a semiconductor and photocatalyst that is also chemically inert. With its bandgap of 3.2 and greater, to activate the photocatalytic property of titania requires light of about 390 nm wavelength, which is in the ultra-violet, where sunlight is very low in intensity. A method and devices are disclosed wherein stress is induced and managed in a thin film of titania in order to shift and lower the bandgap energy into the longer wavelengths that are more abundant in sunlight. Applications of this stress-induced bandgap-shifted titania photocatalytic surface include photoelectrolysis for production of hydrogen gas from water, photovoltaics for production of electricity, and photocatalysis for detoxification and disinfection.