The purpose of the present invention is to provide a formic acid production method and a formic acid production system with high production efficiency and in low cost. It is a formic acid production method comprising: preparing a mixed solution by mixing a solution containing an organic substance with a metal oxide powder having a photocatalyst function; and producing a formic acid by irradiating a light to the mixed solution. Also, it is a formic acid production system comprising: a raw material charging unit into which a solution containing an organic substance and a metal oxide powder having a photocatalyst function are charged; an artificial photosynthesis reaction unit for reacting a mixed solution of the organic substance and the metal oxide powder by irradiating a sunlight or a light to the mixed solution; and a formic acid recovery unit for recovering a formic acid from the mixed solution after an artificial photosynthesis reaction.

A combination of bismuth oxyhalides is provided, which is a photooxidant, antibacterial and antiviral. The combination of bismuth oxyhalides is added to a filter medium (e.g., a multistage filter) to decompose VOCs and/or eliminate bacteria and/or viruses. Suitable designs of multistage filters are also provided.

Porphyrin photosensitizers including 5,15-di(naphthalimide) moieties useful for photocatalytic hydrogen evolution, compositions including the same, and methods of use thereof.

A catalyst adapted for generating hydrogen peroxide induced by a temperature difference and a method for environmental disinfection using the same are provided. The catalyst includes a thermoelectric material distributed on a substrate. The thermoelectric material induces a reaction between water vapor and oxygen contained in the air through a temperature difference to generate hydrogen peroxide, to serve a sterilization function through the hydrogen peroxide generated. The method for environmental disinfection using the catalyst includes the following. The catalyst is placed in an environment with a temperature difference. The catalyst is caused to induce a reaction between water vapor and oxygen contained in air through the temperature difference to generate hydrogen peroxide without applying power, and serve a sterilization function through the hydrogen peroxide generated.

A system includes a display. The display includes an array of LEDs covered by a transparent material. The array of LEDs includes a plurality of first, second, third, and fourth LEDs respectively configured to emit red, green, blue, and violet light. The red, green, and blue light from the first, second, and third LEDs is visible to human eye. Violet light from the fourth LEDs is invisible to human eye. The system includes a photocatalytic coating disposed on the transparent material. The photocatalytic coating includes a photo-catalyst responsive to ultraviolet radiation present in sunlight and to the violet light emitted by the fourth LEDs in the array of LEDs. The system includes a controller configured to selectively turn on the fourth LEDs to activate the photo-catalyst in the photocatalytic coating disposed on the transparent material.

The present invention relates to the field of catalysts, and provides a porous layered transition metal dichalcogenide (TMD) and a preparation method and use thereof. The preparation method includes the following steps: (1) mixing silica microspheres, a transition metal salt and an elemental chalcogen, and pressing to obtain a tablet, the silica microspheres having a same or different particle diameters; and (2) sintering the tablet under hydrogen, and removing the silica microspheres to obtain the porous layered TMD. The porous layered TMD prepared by the method of the present invention has a high lattice edge exposure, which provides more active sites and higher catalytic activity, so the porous layered TMD can effectively catalyze the oxidation of alcohols to aldehydes or sulfides to sulfoxides under visible light irradiation.

Disclosed is a method for manufacturing a photocatalytic filter for air purification. The present manufacturing method comprises the steps of: oxidizing a titanium metal to obtain a nanostructured titanium dioxide (TiO2); adding the nanostructured titanium dioxide to an acidic fluorine-containing solution to allow a reaction to occur therebetween for a predetermined period of time; and, after treatment in the acidic fluorine-containing solution, performing heat treatment on the nanostructured titanium dioxide.

A method is disclosed in which a gas of hydrogen and nitrogen, or hydrogen and ammonia, or hydrogen, nitrogen, and ammonia, is introduced to a fluidized bed. The gas flows through the fluidized bed, and titanium dioxide particles are introduced to the fluidized bed to form a fluid mixture of the particles and gas in the fluidized bed. The particles are reacted with the gas in the fluid mixture to form particles including titanium dioxide and nitrogen. The particles can be disposed along an air flow path in operative communication with a light source for air treatment.

The invention discloses a phosphorus-doped tubular carbon nitride micro-nano material and application thereof in waste gas treatment. Melamine is partially hydrolyzed into cyanuric acid through a phosphorous acid-assisted hydrothermal method to form a melamine-cyanuric acid super molecular precursor; the center of the precursor starts to be pyrolyzed under heating calcination, and thus phosphorus-doped tubular carbon nitride is obtained; the phosphorus-doped tubular carbon nitride and sodium borohydride are mixed and subjected to low-temperature calcination in an inert gas atmosphere, and defect-modified phosphorus-doped tubular carbon nitride is obtained. The defect-modified phosphorus-doped tubular carbon nitride micro-nano material has a good photocatalytic effect on catalytic degradation of waste gas; besides, the production raw materials are abundant and easy to obtain, and the phosphorus-doped tubular carbon nitride micro-nano material is good in stability and recyclable and has application prospects in waste gas treatment.

The present invention relates a deodorizing catalyst including a copper-manganese-based composite oxide, zeolite, and activated carbon.