An air cleaning apparatus includes: a collection filter for collecting dust; a first ultraviolet light emitter for irradiating the collection filter with ultraviolet light having a first wavelength; and a photocatalyst supporting filter which supports a photocatalyst exhibiting photocatalytic activity by the ultraviolet light having the first wavelength and collects the dust. The collection filter transmits the ultraviolet light having the first wavelength, and the ultraviolet light having the first wavelength passing through the collection filter is irradiated to the photocatalyst supporting filter.

Carbon-doped graphitic carbon nitride (g-C.sub.3N.sub.4) compositions are synthesized from the chemical precursors melamine, cyanuric acid and barbituric acid. Phosphorus-doped g-C.sub.3N.sub.4 compositions are synthesized from the chemical precursors melamine, cyanuric acid and etidronic acid. Carbon- and phosphorus-doped g-C.sub.3N.sub.4 compositions, when in the presence of UV or visible light, can be used in water treatment systems to photocatalytically degrade persistent organic micropollutants such as pharmaceuticals and personal care products (PPCPs), endocrine disrupting compounds (EDCs), pesticides, and herbicides. Carbon- and phosphorus-doped g-C.sub.3N.sub.4 compositions can also be applied to surfaces of household and public items to kill protozoa, eukaryotic parasites, algal pathogens, bacteria, fungi, prions, viruses, or other microorganisms, preventing the transfer thereof between users.

Photoactive catalyst and methods of producing H.sub.2 by photocatalytic water splitting. The photoactive catalyst includes an upconverting material, a photocatalyst material, and plasmonic metal nanostructures deposited on the surface of the photocatalyst material. The upconverting material is not embedded in or coated by the photocatalyst material. The upconverting material is capable of emitting light at a first wavelength that has an energy equal to or higher than the band gap of the photocatalyst material and at a second wavelength that can be absorbed by the plasmonic metal nanostructures.

An air purifier includes a housing providing an air path therein, a photocatalyst module disposed in the air path, and an electrostatic dust collector disposed in the air path. The photocatalyst module includes a UV point light source emitting light along a light path, and a photocatalyst net device including at least one spatially curved member disposed in the light path, and having a configuration defined by a specific contour line of equal intensity of the emitted light. The electrostatic dust collector includes a first electrode device and a second electrode device, which have contrary electrical polarities so as to generate an electric field therebetween, and both of which have graphene on surfaces thereof.

Metal-organic frameworks (MOFs) may have Zn(II), Pb(II), and/or Cd(II) as a central metal ion; a 4,4-bipyridylethylene (bpe) ligand as a first ligand; and fumaric acid (fum) and/or oxalic acid (ox) as a second ligand, wherein the 4,4-bipyridylethylene ligands are stacked in the MOF, and wherein a distance between two consecutive 4,4-bipyridylethylene ligands is less than 5 . Cycloadditions, particularly photoinduced [2+2] cycloadditions may be catalyzed by such MOFs, and/or the conversion of photoinduced [2+2] cycloadditions in inventive MOFs may be increased by mechanical force, such as by grinding.

The present invention refers to lightweight and settable photocatalytic compositions and solid composites; methods of preparing the compositions and solid composites; and their use in water purification. The compositions are comprised of photocatalysts such as titanium dioxide (TiO.sub.2) and zinc oxide (ZnO), lightweight glass bubbles, and a hydraulic cementing binder. The lightweight and settable photocatalytic compositions can be formed into lightweight photocatalytic solid composites and/or structures by mixing with water and moist curing. This invention also describes relatively simple, fast, and cost effective methodologies to photodope the TiO.sub.2ZnO compositions and composites with silver (Ag), to enhance and extend the photocatalytic activity from the ultraviolet into the visible light spectrum. The lightweight and settable TiO.sub.2ZnO and AgTiO.sub.2ZnO compositions are used in making solids, structures, coatings, and continuous or semi-continuous water purification panels for purifying contaminated water.

A water treatment system with a photocatalytic nanocomposite sheet, an adsorbent layer, and a fibrous filter, wherein the photocatalytic nanocomposite sheet comprises polymethylmethacrylate and silver phosphate, the adsorbent layer comprises plasma activated carbon nanotubes, and the fibrous filter is a composite of polymethylmethacrylate, polyvinylidene fluoride, and polyvinylpyrrolidone polymer fibers, with carbon nanotubes that are dispersed within the polymer fibers and silver nanoparticles that are deposited on the polymer fibers. Various embodiments of the water treatment system and methods of fabricating the photocatalytic nanocomposite sheet, the adsorbent layer, and the fibrous filter are also provided.

The present disclosure provides a photocatalyst filter that can efficiently decompose and eliminate ozone gas or VOC and has a low ventilation resistance. The photocatalyst filter includes a sheet-like filter substrate and a photocatalyst layer supported by the filter substrate. The photocatalyst layer exhibits a photocatalytic action by receiving light having a wavelength of 400 nm or more. The photocatalyst filter has an aperture ratio of 35% or more and 80% or less.

A self-cleaning film system includes a substrate and an anti-reflection film disposed on the substrate. The anti-reflection film includes a first sheet formed from titanium dioxide, a second sheet formed from silicon dioxide and disposed on the first sheet, and a third sheet formed from titanium dioxide and disposed on the second sheet. The system includes a self-cleaning film disposed on the anti-reflection film and including a monolayer disposed on the third sheet and formed from a fluorinated material selected from the group consisting of fluorinated organic compounds, fluorinated inorganic compounds, and combinations thereof. The self-cleaning film includes a first plurality of regions disposed within the monolayer such that each of the first plurality of regions abuts and is surrounded by the fluorinated material and includes a photocatalytic material.

A photocatalytic member comprises a base and a photocatalytic layer fixed on the base. The photocatalytic layer comprises first photocatalyst particles being visible light responsive photocatalyst particles for hydrogen generation, second photocatalyst particles being visible light responsive photocatalyst particles for oxygen generation, and conductive particles which are provided between the first photocatalyst particle and the second photocatalyst particle, have Fermi level at a negative position relative to an electronic energy level at the upper end of the valence band of the first photocatalyst particle and at a positive position relative to an electronic energy level at the bottom end of the conduction band of the second photocatalyst particle, and are able to store an electron and a hole. In the photocatalytic layer, the conductive particles are located to be coupled to both the first photocatalyst particles and the second photocatalyst particles.