Embodiments of the present invention include a filter element for decomposing contaminants including a substrate, and a photocatalytic composition comprising at least a photocatalyst and a co-catalyst. The embodiments of the present invention also includes a system for decomposing contaminants including a substrate, and a photocatalytic composition comprising at least a photocatalyst and a co-catalyst; and a method using the system.

Embodiments of the present invention include a filter element for decomposing contaminants including a substrate, and a photocatalytic composition comprising at least a photocatalyst and a co-catalyst. The embodiments of the present invention also includes a system for decomposing contaminants including a substrate, and a photocatalytic composition comprising at least a photocatalyst and a co-catalyst; and a method using the system.

A method of turning a catalytic material by altering the charge state of a catalyst support. The catalyst support is intercalated with a metal ion, altering the charge state to alter and/or augment the catalytic activity of the catalyst material.

A method of turning a catalytic material by altering the charge state of a catalyst support. The catalyst support is intercalated with a metal ion, altering the charge state to alter and/or augment the catalytic activity of the catalyst material.

Provided is a method for producing a photocatalyst electrode for water decomposition that exhibits excellent detachability between the substrate and the photocatalyst layer and exhibits high photocurrent density. The method for producing a photocatalyst electrode for water decomposition of the invention includes: a metal layer forming step of forming a metal layer on one surface of a first substrate by a vapor phase film-forming method or a liquid phase film-forming method; a photocatalyst layer forming step of forming a photocatalyst layer by subjecting the metal layer to at least one treatment selected from an oxidation treatment, a nitriding treatment, a sulfurization treatment, or a selenization treatment; a current collecting layer forming step of forming a current collecting layer on a surface of the photocatalyst layer, the surface being on the opposite side of the first substrate; and a detachment step of detaching the first substrate from the photocatalyst layer.

Provided is a method for producing a photocatalyst electrode for water decomposition that exhibits excellent detachability between the substrate and the photocatalyst layer and exhibits high photocurrent density. The method for producing a photocatalyst electrode for water decomposition of the invention includes: a metal layer forming step of forming a metal layer on one surface of a first substrate by a vapor phase film-forming method or a liquid phase film-forming method; a photocatalyst layer forming step of forming a photocatalyst layer by subjecting the metal layer to at least one treatment selected from an oxidation treatment, a nitriding treatment, a sulfurization treatment, or a selenization treatment; a current collecting layer forming step of forming a current collecting layer on a surface of the photocatalyst layer, the surface being on the opposite side of the first substrate; and a detachment step of detaching the first substrate from the photocatalyst layer.

An object of the present invention is to provide a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutene, which enables a catalyst demonstrating favorable yield to be stably produced. According to the present invention, there is provided a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutane, comprising the steps of: (i) preparing a catalyst raw material mixture containing Mo, V and Nb and satisfying the relationships of 0.1≦a≦1 and 0.01≦b≦1 when atomic ratios of V and Nb to one atom of Mo are defined as a and b, respectively; (ii) drying the catalyst raw material mixture; and (iii) calcining a particle, in which a content of the particle having a particle diameter of 25 μm or less is 20% by mass or less and a mean particle diameter is from 35 to 70 μm, in an inert gas atmosphere.

An object of the present invention is to provide a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutene, which enables a catalyst demonstrating favorable yield to be stably produced. According to the present invention, there is provided a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutane, comprising the steps of: (i) preparing a catalyst raw material mixture containing Mo, V and Nb and satisfying the relationships of 0.1≦a≦1 and 0.01≦b≦1 when atomic ratios of V and Nb to one atom of Mo are defined as a and b, respectively; (ii) drying the catalyst raw material mixture; and (iii) calcining a particle, in which a content of the particle having a particle diameter of 25 μm or less is 20% by mass or less and a mean particle diameter is from 35 to 70 μm, in an inert gas atmosphere.

The exhaust gas-purifying catalyst of the invention includes a noble metal, and crystallites that form CZ composite metal particles which serve as a carrier supporting the noble metal and contain at least zirconium (Zr) and cerium (Ce). The CZ composite oxide particles (crystallites) further contain crystal growth-suppressing fine particles which are fine metal particles comprising primarily a metallic element M that melts at 1,500° C. or above and which suppress crystal growth by the CZ composite oxide particles. The content of the metallic element M included in the CZ composite oxide particles, expressed in terms of the oxide thereof, is 0.5 mol % or less of the total oxide.

The exhaust gas-purifying catalyst of the invention includes a noble metal, and crystallites that form CZ composite metal particles which serve as a carrier supporting the noble metal and contain at least zirconium (Zr) and cerium (Ce). The CZ composite oxide particles (crystallites) further contain crystal growth-suppressing fine particles which are fine metal particles comprising primarily a metallic element M that melts at 1,500° C. or above and which suppress crystal growth by the CZ composite oxide particles. The content of the metallic element M included in the CZ composite oxide particles, expressed in terms of the oxide thereof, is 0.5 mol % or less of the total oxide.