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.