Abstract: To provide a novel visible light-responsive photocatalyst or tungsten oxide visible light-responsive semiconductor improved in environmental resistance under an alkaline condition. The tungsten oxide visible light-responsive semiconductor unstable under an alkaline condition is improved in environmental resistance without losing photocatalytic function thereof by adding thereto at least one element selected from the group consisting of copper, tantalum, niobium, lanthanum, bismuth, calcium, chromium, manganese and zinc. The obtained environmental resistant visible light-responsive photocatalyst is subjected to an alkaline treatment to thereby be improved in photocatalytic activity.

Abstract: To provide a novel visible light-responsive photocatalyst or tungsten oxide visible light-responsive semiconductor improved in environmental resistance under an alkaline condition. The tungsten oxide visible light-responsive semiconductor unstable under an alkaline condition is improved in environmental resistance without losing photocatalytic function thereof by adding thereto at least one element selected from the group consisting of copper, tantalum, niobium, lanthanum, bismuth, calcium, chromium, manganese and zinc. The obtained environmental resistant visible light-responsive photocatalyst is subjected to an alkaline treatment to thereby be improved in photocatalytic activity.

Abstract: The semiconductor photoelectrode of the present invention includes a metallic substrate having irregularities in a surface and a semiconductor layer which is formed on the surface of the metallic substrate and composed of a photocatalytic material. This can increase the light absorption efficiency and, furthermore, prevent recombination of charges.

Abstract: The semiconductor photoelectrode of the present invention includes a metallic substrate having irregularities in a surface and a semiconductor layer which is formed on the surface of the metallic substrate and composed of a photocatalytic material. This can increase the light absorption efficiency and, furthermore, prevent recombination of charges.

Abstract: A semiconductor film electrode using a specific organic dye sensitizer, a high efficiency dye-sensitized photovoltaic conversion element using the electrode, and a dye-sensitized photoelectrochemical solar cell using the element are described. The semiconductor film electrode is characterized by including a semiconductor sensitized with an organic dye having a structure represented by the following formula (1): wherein Z represents a heterocyclic group which may have a substituent, L represents an electron attractive group, R1-R3 each represent a hydrogen atom or a substituent or adjacent two of R1-R3 are taken in combination to represent a ring, M represents a hydrogen atom or a salt-forming cation, and n is an integer of 0 to 3.

Abstract: A photocatalyst including a metal oxide semiconductor represented by the formula: In1?xMxAO4 wherein M represents a transition metal element, A represents an element belonging to the Group 5a of the Periodic Table and x is a number greater than 0 but smaller than 1.

Abstract: A semiconductor film electrode using a specific organic dye sensitizer, a high efficiency dye-sensitized photovoltaic conversion element using the electrode, and a dye-sensitized photoelectrochemical solar cell using the element are described.

Abstract: A process for making a pattern according to intended design on cloth or clothing, particularly denim clothing, dyed with a colorant or a dye through decolorizing is provided. Fabric or clothing dyed with a colorant or a dye is impregnated with a substance forming an oxidized active species upon electrolysis and inserted between a pair of electrodes, and electricity is applied to the electrodes, whereby only a part where electricity is applied is selectively decolorized to make a pattern with gradated effect.

Abstract: A photocatalyst including a metal oxide semiconductor represented by the formula:

Abstract: A process for making a pattern according to intended design on cloth or clothing, particularly denim clothing, dyed with a colorant or a dye through decolorizing is provided. Fabric or clothing dyed with a colorant or a dye is impregnated with a substance forming an oxidized active species upon electrolysis and inserted between a pair of electrodes, and electricity is applied to the electrodes, whereby only a part where electricity is applied is selectively decolorized to make a pattern with gradated effect.

Abstract: A metal complex represented by the formula: (X)nML1L2, (X)2M(L1)2 or (L1)2ML2 wherein M represents a Group VIII metal, X represents a polar group, L1 represents a phenanthroline containing at least one carboxyl group which may be neutralized, L2 represents a nitrogen-containing polycyclic compound which may contain one or more substituents, and n is an integer of 1 or 2. A dye-sensitized oxide semiconductor electrode includes an electrically conductive body, an oxide semiconductor film provided on a surface of the electrically conductive body, and the above metal complex. A solar cell may be constructed from the above dye-sensitized oxide semiconductor electrode, a counter electrode, and a redox electrolyte contacting with both electrodes.

Abstract: A platinum complex represented by the formula PtL1/L2 or PtLX1/LX2 wherein L1 and L each represent a ligand selected from the group consisting of 2,2′-bipyridine compounds having at least one anionic group and 1,10-phenanthroline compounds having at least one anionic group, L2 represents a dithiolate selected from those represented by the formulas (a) through (d) shown in the specification, and X1 and X2 each represent a thiolate selected from those represented by the following formulas (e) and (f) shown in the specification. A dye-sensitized electrode includes a substrate having an electrically conductive surface, an oxide semiconductor film formed on the conductive surface, and the above platinum complex supported on the film. A solar cell includes the above electrode, a counter electrode, and an electrolyte disposed therebetween.

Abstract: A catalyst for methanol synthesis and reforming which is constituted of copper, zinc, and aluminum oxides and has a structure comprising copper or copper oxide particles covered with a film of aluminum oxide and zinc oxide. The copper or copper oxide particles preferably have a particle size of 1 to 100 nm. The film of aluminum oxide and zinc oxide preferably has a thickness of 0.1 to 100 nm. The proportions of the copper, zinc, and aluminum elements are 68.0 to 86.0% by weight, 4.5 to 21.0% by weight, and 2.0 to 20.0% by weight, respectively. The foregoing highly active catalyst comprising copper, zinc, and aluminum oxides can be obtained not by a costly special technique but by the coprecipitation method, which is the most common process for catalyst production, without using any additive element.

Abstract: A process for the production of a hydrogen gas from water, wherein comprising an aqueous solution containing ferric ions is irradiated with a light while maintaining the aqueous solution in contact with a photocatalyst to convert the ferric ions into ferrous ions. The resulting aqueous solution containing the ferrous ions is electrolyzed to yield a hydrogen gas.

Abstract: There is disclosed a method for producing hydrogen and oxygen photocatalytically from water, which comprises bringing an aqueous solution of carbonate into contact with a semiconductor carrying a metal or a metal compound and irradiating the aqueous solution with light.