The present invention provides a preparation method of a photocatalytic composite material, and relates to the field of catalyst technologies. The preparation method provided in the present invention includes the following steps: (1) subjecting plant leaves to soaking pretreatment to obtain template biomass; (2) mixing a molybdenum source-sulfur source aqueous solution with the template biomass obtained in step (1) and conducting impregnation to obtain a composite material precursor; and (3) calcining the composite material precursor obtained in step (2) to obtain the photocatalytic composite material. The photocatalytic composite material in the present invention includes acicular molybdenum sulfide and biomass carbon, the acicular molybdenum sulfide is loaded to a surface of the flake carbon, the mass content of the biomass carbon is 70% to 90%, and the mass content of the molybdenum sulfide is 10% to 30%. Performance of photocatalytic hydrogen production of the photocatalytic composite material in the present invention is better than that of a pure molybdenum sulfide material and has excellent photocorrosion resistance, and hydrogen production efficiency is reduced by only approximately 10% after three cycles.

The present invention provides a preparation method of a photocatalytic composite material, and relates to the field of catalyst technologies. The preparation method provided in the present invention includes the following steps: (1) subjecting plant leaves to soaking pretreatment to obtain template biomass; (2) mixing a molybdenum source-sulfur source aqueous solution with the template biomass obtained in step (1) and conducting impregnation to obtain a composite material precursor; and (3) calcining the composite material precursor obtained in step (2) to obtain the photocatalytic composite material. The photocatalytic composite material in the present invention includes acicular molybdenum sulfide and biomass carbon, the acicular molybdenum sulfide is loaded to a surface of the flake carbon, the mass content of the biomass carbon is 70% to 90%, and the mass content of the molybdenum sulfide is 10% to 30%. Performance of photocatalytic hydrogen production of the photocatalytic composite material in the present invention is better than that of a pure molybdenum sulfide material and has excellent photocorrosion resistance, and hydrogen production efficiency is reduced by only approximately 10% after three cycles.

Method and photo-electrochemical system using Cu(In,Ga)Se.sub.2 CIGS for reducing electrochemically CO.sub.2 into CO using as catalyst a metal complex with quaterpyridine ligand, the electrochemical cell comprising a cathode, an anode, a cathodic electrolyte comprising water as the solvent, and a power supply providing the energy necessary to trigger the electrochemical reactions.

Method and photo-electrochemical system using Cu(In,Ga)Se.sub.2 CIGS for reducing electrochemically CO.sub.2 into CO using as catalyst a metal complex with quaterpyridine ligand, the electrochemical cell comprising a cathode, an anode, a cathodic electrolyte comprising water as the solvent, and a power supply providing the energy necessary to trigger the electrochemical reactions.

Methods of making catalyst electrodes comprising sputtering at least Pt and Ir onto nanostructured whiskers to provide multiple alternating layers comprising, respectively in any order, at least Pt and Ir. In some exemplary embodiments, catalyst electrodes described, or made as described, herein are anode catalyst, and in other exemplary embodiments cathode catalyst. Catalysts electrodes are useful, for example, in generating H.sub.2 and O.sub.2 from water.

A radiation-assisted (typically solar-assisted) electrolyzer cell and panel for high-efficiency hydrogen production comprises a photoelectrode and electrode pair, with said photoelectrode comprising either a photoanode electrically coupled to a cathode shared with an anode, or a photocathode electrically coupled to an anode shared with a cathode; electrolyte; gas separators; all within a container divided into two chambers by said shared cathode or shared anode, and at least a portion of which is transparent to the electromagnetic radiation required by said photoanode (or photocathode) to apply photovoltage to a shared cathode (or anode) that increases the electrolysis current and hydrogen production.

Systems and methods for providing alternative fuel, in particular hydrogen photocatalytically generated by a system comprising photoactive nanoparticles and a nitrogenase cofactor are provided. In one aspect, the system includes a water soluble cadmium selenide nanoparticle (CdSe) surface capped with mercaptosuccinate (CdSe-MSA) and a NafY.FeMo-co complex comprising a NafY protein and an iron-molybdenum cofactor (FeMo-co), wherein the CdSe-MSA and NafY.FeMo-co complex are present in about 1:2 to 1:10 molar ratio.

An object of the present invention is to provide a photocatalyst for water splitting, which can form a water splitting device that is excellent in durability and responsiveness to visible light and excellent in the amount of generated gas, and a water splitting device having the photocatalyst for water splitting. A photocatalyst for water splitting according to the embodiment of the present invention is a photocatalyst for water splitting, which is used for an electrode that generates gas by irradiation with light in a state of being immersed in water, and includes a compound represented by a formula, (Ln).sub.2CuO.sub.4. In the formula, Ln represents a lanthanoid, and a part of Ln's may be substituted with an element of Groups II to IV of the periodic table.

The present disclosure provides a semiconductor compound, which includes a metal complex unit and a conjugate unit. The metal complex unit includes a coordination center and a plurality of ligands. The coordination center is a metal ion or a metal atom, and the ligands are linked with the coordination center. The conjugate unit is linked with the metal complex unit by covalent bond.

An object of the present invention is to provide a photocatalytic electrode for water splitting and a water splitting device excellent in the onset potential. The water splitting device of the present invention is a water splitting device which generates gases from a photocatalytic electrode for hydrogen generation and a photocatalytic electrode for oxygen generation by irradiating the photocatalytic electrode for hydrogen generation and the photocatalytic electrode for oxygen generation with light, and includes a bath to be filled with an electrolytic aqueous solution and the photocatalytic electrode for hydrogen generation and the photocatalytic electrode for oxygen generation each disposed in the bath. The photocatalytic electrode for hydrogen generation has a p-type semiconductor layer, an n-type semiconductor layer provided on the p-type semiconductor layer, and a co-catalyst provided on the n-type semiconductor layer. The p-type semiconductor layer is a semiconductor layer containing a CIGS compound semiconductor containing Cu, In, Ga, and Se, and a molar ratio of Ga to a total molar amount of Ga and In in the CIGS compound semiconductor is 0.4 to 0.8.