TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: In the step (c) the hydrogen titanates are annealed in air to obtain anatase nanofibers prior to annealing in ammonia. The obtained titanium dioxide nanofibers are further dispersed with liquids or cellulose fibers in liquids, where the dispersion is applied to a surface and dried to obtain a photocatalyst material membrane, film or coating. Preferred Components: The titanium dioxide nanofibers contain alkali metal impurities. The high work function material is a metal comprising silver, gold or platinum group metal including platinum, palladium, rhodium or iridium. The semi-conductor nanoparticle is cobalt(II,III) oxide, cupric oxide, nickel oxide, dichromium trioxide, copper sulfide/cadmium sulfide, cuprous oxide,II-VI semiconductors (zinc oxide, zinc sulfide, zinc selenide, cadmium sulfide, cadmium selenide, cadmium telluride, mercury sulfide, mercury selenide, mercury telluride), or silicon, germanium or other compound semiconductors which make p-n junctions with titanium dioxide and with N-doped titanium dioxide. The titanium dioxide nanofiber is a particle having at least one dimension less than 100 nm, such as a nanofiber having the length of 0.2-10 mu m and the diameter in of 10-100 nm, such as the length of 1 mu m and the diameter of 50 nm.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The high work function material is a form of carbon e.g. carbon nanotube, graphene, amorphous carbon or fullerene.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The high work function material is a conductive polymer e.g. poly-thiophene, poly-acetylene or poly-pyrrole. The photocatalyst material is a composite with synthetic polymer, biopolymer or inorganic material. The synthetic polymer is a step-growth polymer e.g. polyamide, polyacetal, polyester, nylon, bakelite or a chain-growth polymer e.g. polyethylene, polypropylene, polyvinyl chloride, polystyrene, neoprene or synthetic rubber. The biopolymer is polysaccharide, e.g. celluloses and their derivatives, hemicellulose, starch, glycogen, chitin or polypeptide e.g. wool, silk or other polymer (e.g. lignin or polyisoprene). The inorganic material is ceramic-type materials, clays, cements, silicates and alumino-silicates balanced with several type of alkali, earth and transition metal cations, transition and earth metal oxides, boron oxides and their alloys, mica, feldspar, carbides and nitrides of silicon and boron and various forms of alumina, and hetero-atomic polymers including: polyborazylenes; polysiloxanes, polysilazanes, polyphosphazenes, polythiazyls or polysulfides; perfluorated; or chlorinated polymers with or without oxygen-containing functional groups. The starting material is water, alcohol, alcohol/water mixture, or other organic compound e.g. hydrocarbon or oxygen-containing organic molecule. EXAMPLE - No suitable example given.