The present investigation is development of the TiO.sub.2 nanotubes concept of preparation of and their composite with fine dispersion of copper. The inventions also relates to identify a method for optimum amount of photocatalyst required for efficient and maximum hydrogen production reported than earlier (H.sub.2=99,823 μmol.Math.h.sup.−1.Math.g.sup.−1 catalyst) from glycerol-water mixtures under solar light irradiation. A method is disclosed to produce CuO/TiO.sub.2 nanotubes with high sustainability and recyclable activity for hydrogen production.

A photocatalyst and a method for producing hydrogen and oxygen from water by photocatalytic electrolysis are disclosed. The photocatalyst includes a photoactive material and metal or metal alloy material (15)—e.g. pure particles or alloys of Au, Pd and Ag—capable of having plasmon resonance properties deposited on the surface of the photoactive material. The photoactive material includes a p-n junction (17) formed by contact of a n-type semiconductor material (10), such as mixed phase TiO2 nano particles (anatase to rutile ratio of 1.5 to 1 or greater), and a p-type semiconductor material (16), such as CoO or Cu2O.

The present invention provides a method of producing a composite photocatalyst having a remarkable water splitting activity, which is capable of efficiently loading a co-catalyst having a small particle size in a highly dispersed manner on a surface of an optical semiconductor. According to the present invention, the method of producing a composite photocatalyst from a plurality types of optical semiconductors includes a step of heating a solid-liquid mixture containing a solvent, a co-catalyst or a co-catalyst source, and a plurality of types of optical semiconductors by irradiating the solid-liquid mixture with microwave.

Disclosed is a photocatalyst, and methods for its use, that includes a photoactive material comprising a photonic band gap and an electronic band gap, wherein the photonic band gap at least partially overlaps with the electronic band gap, and an electrically conductive material deposited on the photoactive material.

A system and method are provided in at least one embodiment to process water to produce gas that can be separated into at least two gas flows using a water treatment system having a disk-pack rotating in it to cause out gassing from the water. In a further embodiment, the method and system use the gas released from the water to produce substantially fresh water from the processed salt water.

A photocatalyst powder is provided. The photocatalyst powder includes a plurality of nano crystallite aggregates formed by a plurality of nano crystallites. Each of the nano crystallites exhibits a single crystal structure. The nano crystallites have different compositions, different crystal phases, and different lattice constants from each other. An example of the nano crystallites is represented as the formula of ZnO.sub.1-xS.sub.x with different x values in each of the nano crystallites. In addition, a hydrogen producing system is also provided.

A composite material for photocatalytic hydrogen production and a photocatalytic hydrogen production catalyst are provided. The composite material includes a plurality of inorganic semiconductor particles and a linear conjugated polymer material. The conductive band of a material of the inorganic semiconductor particles is higher than the reduction potential of hydrogen, and the linear conjugated polymer material is compounded on a surface of each of the inorganic semiconductor particles, wherein the difference in the energy level of the lowest unoccupied molecular orbital (LUMO) of the linear conjugated polymer material and the conductive band of the material of the inorganic semiconductor particles is within 2 eV.

InGaN offers a route to high efficiency overall water splitting under one-step photo-excitation. Further, the chemical stability of metal-nitrides supports their use as an alternative photocatalyst. However, the efficiency of overall water splitting using InGaN and other visible light responsive photocatalysts has remained extremely low despite prior art work addressing optical absorption through band gap engineering. Within this prior art the detrimental effects of unbalanced charge carrier extraction/collection on the efficiency of the four electron-hole water splitting reaction have remained largely unaddressed. To address this growth processes are presented that allow for controlled adjustment and establishment of the appropriate Fermi level and/or band bending in order to allow the photochemical water splitting to proceed at high rate and high efficiency. Beneficially, establishing such material surface charge properties also reduces photo-corrosion and instability under harsh photocatalysis conditions.

An electromagnetic resonance apparatus for molecular, atomic, and chemical modification of water is provided. The apparatus includes a water container, a resonance induction cell tower, an electronic control unit, a 12-volt power source, a DC to AC power inverter, and a pressure vessel for storing produced hydrogen gas. An electronic control unit is used to provide vibrational energy to the cell tower to facilitate water decomposition.

Disclosed is a visible light responsive photocatalyst that simultaneously realizes high crystallinity and refinement of primary particles. Also disclosed is a photocatalyst composed of secondary particles that have a high porosity and are aggregates of fine primary particles. Rhodium-doped strontium titanate that is a visible light responsive photocatalyst of the present invention has a primary particle diameter of not more than 70 nm and has a absorbance at a wavelength of 570 nm of not less than 0.6 and a absorbance at a wavelength of 1800 nm of not more than 0.7, each absorbance determining by measuring a diffuse reflection spectrum, the rhodium-doped strontium titanate having a high water-splitting activity as a photocatalyst.