Abstract: The cocatalyst for hydrogen generation is a cocatalyst for hydrogen generation to be combined with a semiconductor catalyst that is excited by light and includes a metal-organic framework having a molecular structure represented by the following formula (1). In the formula (1), M is at least one selected from Ni, Co, Fe, Cu, Zn, Pd, Pt, Au, and Ir, L1 to L4 are each independently at least one selected from S, Se, Te, NH, and O, C1 and C2 are carbon atoms forming a first aromatic group, and C3 and C4 are carbon atoms forming a second aromatic group.

Abstract: In a photocatalyst and a photocatalyst carrier, tungsten oxide microcrystals that have a crystal grain size of 10 nm or less and oxidizes a gaseous chemical substance and titanium oxide microcrystals that have a crystal grain size of 10 nm or less and oxidizes the gaseous chemical substance are irregularly arranged to form a solid.

Abstract: In a photocatalyst and a photocatalyst carrier, tungsten oxide microcrystals that have a crystal grain size of 10 nm or less and oxidizes a gaseous chemical substance and titanium oxide microcrystals that have a crystal grain size of 10 nm or less and oxidizes the gaseous chemical substance are irregularly arranged to form a solid.

Abstract: The present invention provides a method for fabricating an electrode comprising a co-catalyst layer for splitting water with light. The method comprises steps of (a) forming a catalyst layer containing at least one selected from the group consisting of a niobium-containing oxynitride and a niobium-containing nitride on an electrically conductive principal surface of a substrate; (b) forming a transition metal oxide layer on the catalyst layer in an inert gas atmosphere containing oxidized gas impurities to provide a stacking structure comprising the substrate, the catalyst layer, and the transition metal oxide layer; (c) immersing the stacking structure in an electrolyte aqueous solution; and (d) applying a positive electric potential to the stacking structure in the electrolyte aqueous solution to convert the transition metal oxide layer into the co-catalyst layer. The present invention provides an electrode for water splitting having high water-splitting efficiency.

Abstract: Disclosed are: a catalyst which is capable of reducing and converting nitrate ions into ammonia without adding a hydrogen gas thereto; a method for synthesizing ammonia using the catalyst, wherein nitrate ions are reduced without adding a hydrogen gas thereto; and a method for decreasing nitrogen oxide in water by reducing nitrate ions contained in the water. Disclosed is a photocatalyst composition that is obtained by loading a photocatalyst, which is capable of photoreducing protons into a hydrogen gas, with CuPd alloy nanoparticles. The photocatalyst composition is used for the purpose of producing ammonia by photoreducing nitrogen that is coexistent with water and nitrogen oxide. The CuPd alloy nanoparticles are (1) CuPd alloy nanoparticles having a B2 type crystal structure and represented by CuxPd(1-x) (wherein 0.3?x?0.7), (2) CuPd alloy nanoparticles having a bcc type crystal structure and represented by CuxPd(1-x) (wherein 0.3<x<0.

Abstract: Disclosed are: a catalyst which is capable of reducing and converting nitrate ions into ammonia without adding a hydrogen gas thereto; a method for synthesizing ammonia using the catalyst, wherein nitrate ions are reduced without adding a hydrogen gas thereto; and a method for decreasing nitrogen oxide in water by reducing nitrate ions contained in the water. Disclosed is a photocatalyst composition that is obtained by loading a photocatalyst, which is capable of photoreducing protons into a hydrogen gas, with CuPd alloy nanoparticles. The photocatalyst composition is used for the purpose of producing ammonia by photoreducing nitrogen that is coexistent with water and nitrogen oxide. The CuPd alloy nanoparticles are (1) CuPd alloy nanoparticles having a B2 type crystal structure and represented by CuxPd(1-x) (wherein 0.3<x<0.7), (2) CuPd alloy nanoparticles having a bcc type crystal structure and represented by CuxPd(1-x) (wherein 0.3<x<0.

Abstract: To provide a tungsten oxide photocatalyst which shows a high photocatalytic activity by irradiating with visible light even under the environment where ultraviolet light is not irradiated, the tungsten oxide photocatalyst has tungsten oxide particles and Pt particles having a primary particle size of 3 to 20 nm supported on the surface of the tungsten oxide particles in an amount of 0.03 to 5 parts by weight based on 100 parts by weight of the tungsten oxide particles.

Abstract: A method for producing a photocatalytic, which can produce a photocatalyst showing high photocatalytic activity, is provided. The present invention relates to a method for producing noble metal-supported photocatalyst particles wherein a noble metal is supported on the surface of the photocatalyst particles, and a method for producing a dispersion of the noble metal-supported photocatalyst particles, the methods comprising steps of: blowing an inert gas into a raw dispersion in which the photocatalyst particles are dispersed and a precursor of the noble metal is dissolved in a dispersion medium; and irradiating the raw dispersion with light having energy larger than that of a bandgap of the photocatalyst particles, thereby supporting the noble metal on the surface of the photocatalyst particles.

Abstract: According to the present invention, two hydroxyl groups can be introduced into the 1-position and the 4-position of the benzene ring of an aromatic compound highly efficiently and highly selectively by a one step process to give the corresponding aromatic hydroxide. The present invention provides a production method of an aromatic hydroxide represented by the formula (2) wherein R1, R2, R3, and, R4 are each independently a hydrogen atom or an alkyl group having a carbon atom number of 1-20, and R1, R2 and/or R3 and R4 are optionally bonded to each other to form a ring, which comprises irradiating light to a photoelectrode comprised of metal oxide while applying a given potential in the presence of an aromatic compound represented by the formula (1) wherein R1, R2, R3, and R4 are as defined above.

Abstract: According to the present invention, two hydroxyl groups can be introduced into the 1-position and the 4-position of the benzene ring of an aromatic compound highly efficiently and highly selectively by a one step process to give the corresponding aromatic hydroxide. The present invention provides a production method of an aromatic hydroxide represented by the formula (2) wherein R1, R2, R3, and, R4 are each independently a hydrogen atom or an alkyl group having a carbon atom number of 1-20, and R1, R2 and/or R3 and R4 are optionally bonded to each other to form a ring, which comprises irradiating light to a photoelectrode comprised of metal oxide while applying a given potential in the presence of an aromatic compound represented by the formula (1) wherein R1, R2, R3, and R4 are as defined above.

Abstract: To provide a tungsten oxide photocatalyst which shows a high photocatalytic activity by irradiating with visible light even under the environment where ultraviolet light is not irradiated, the tungsten oxide photocatalyst has tungsten oxide particles and Pt particles having a primary particle size of 3 to 20 nm supported on the surface of the tungsten oxide particles in an amount of 0.03 to 5 parts by weight based on 100 parts by weight of the tungsten oxide particles.