A composition of a photocatalyst, a method of manufacturing the photocatalyst, and a method of chemically reducing carbon dioxide to carbon monoxide using the photocatalyst under visible-light irradiation is provided. The photocatalyst comprises a transition metal ion and graphitic carbon nitride and includes single metal sites on carbon nitride. Under visible light, the metal sites that are coordinated to nitrogen atoms get activated, without the use of additional ligands, to catalyze the reduction of carbon dioxide to selectively produce carbon monoxide. The photocatalytic reduction of carbon dioxide to carbon monoxide is highly efficient, resulting a turnover number of more than 800 for carbon monoxide production in 2 hours. The composition is useful in converting carbon dioxide into useful chemicals and carbon-based fuels. A functional model of molecular catalysts for efficient carbon dioxide reduction is also present.

A radioactive cesium adsorbent includes photocatalyst particles and Prussian blue. The ferric ions of the Prussian blue are reduced to ferrous ions by activation of the photocatalyst particles. A method of removing radioactive cesium using the radioactive cesium adsorbent includes preparing a composition comprising photocatalyst particles and Prussian blue; preparing a precursor solution by mixing radioactive cesium and the composition prepared in the preparing of a composition; and reducing ferric ions of the Prussian blue to ferrous ions by activating the photocatalyst particles in the precursor solution prepared in the preparing of a precursor solution.

The invention provides a titanium carbide nanosheet/layered indium sulfide heterojunction and an application of the same in degrading and removing water pollutants. A simple electrostatic self-assembly method is used to uniformly absorb indium ions on the surfaces of Ti.sub.3C.sub.2 nanosheets, which effectively inhibits the stacking of the nanosheets and is beneficial to the uniform growth of In.sub.2S.sub.3 nanosheets on the surfaces of the Ti.sub.3C.sub.2. The present invent overcomes two disadvantages of too fast photogenerated carrier recombination rate of In.sub.2S.sub.3 and easy agglomeration of nano-scale In.sub.2S.sub.3, and effectively improves the separation efficiency and photocatalytic activity of photogenerated electron-hole of In.sub.2S.sub.3.

A photocatalyst filter is provided. The photocatalyst filter includes: a base in which an internal space is formed. The internal space is permeable to fluid, and a plurality of photocatalyst beads are provided in the internal space, wherein a surface of the internal space is reflective.

Materials for binding per- and polyfluoroalkyl substances (PFAS) are disclosed. A fluidic device comprising the materials for detection and quantification of PFAS in a sample is disclosed. The fluidic device may be configured for multiplexed analyses. Also disclosed are methods for sorbing and remediating PFAS in a sample. The sample may be groundwater containing, or suspected of containing, one or more PFAS.

Photocatalytic materials with a composite photocatalyst of a metal oxide impregnated with elemental metal particles, can be embedded into a hydrophilic polymer having pores with diameters of less than 2 nm, to provide a useful water remediation and/or purification product. The metal oxide may be WO.sub.3, CeO.sub.2, Bi.sub.2O.sub.3, NiO, TiO.sub.2, and/or ZnO, and the elemental metal particles, impregnated or compounded into the metal oxide, may be Fe, Co, Ni, Cu, Ag, Ce, Mn, Mo, V, Bi, Sn, W, Nb, Pd, and/or Pt. The photocatalytic materials may be easily removed and/or retrieved after use, and can effectively combat both chemical and biological contamination and/or fouling of water as well as the membranes composed of the photocatalytic material.

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.

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.

A method for the preparation of zirconia-multi-walled carbon nanotube nanocomposite utilizing Pluronics as templating agents is described. An efficient method for producing hydrogen gas using the nanocomposite as a photocatalyst.

An air conditioning device is disclosed. The present air conditioning device comprises: a photocatalytic filter including a space through which air can pass and having a transition metal oxide formed in a nanotube form on the surface thereof, the transition metal oxide removing gases included in the air and including at least one of TiO.sub.2, ZnO, NiO, and WO.sub.3; and a light source for emitting light to the photocatalytic filter.