A method of preparing large-size high-porosity Fe-doped photocatalytic porous magnetic microspheres, including: dissolving a soluble macromolecule in a distilled water to obtain a solution A having a concentration of 0.5-1.5 wt %; adding a photocatalyst to the solution A, and uniformly stirring the solution A to obtain a suspension B; mixing a saturated soluble ferric salt solution with the suspension B, and uniformly stirring the mixture to obtain a suspension C; dropwise adding the suspension C to a high-concentration alkali solution by a syringe equipped with a suitable needle size to form microspheres; ageing the reaction system and drying the formed microspheres after adding; calcining the dried microspheres at 600-1100 C.; cooling the calcined microspheres to obtain the large-size high-porosity Fe-doped photocatalytic porous magnetic microspheres.

A battery includes an electrode group including an air electrode and a negative electrode stacked with a separator therebetween, and an accommodating bag accommodating the electrode group along with an alkali electrolyte solution. The air electrode includes a catalyst for an air secondary battery. This catalyst for an air secondary battery is produced by a method for producing a catalyst for an air secondary battery, the method including a precursor preparation step of preparing a bismuth-ruthenium oxide precursor, a calcination step of calcining the bismuth-ruthenium oxide precursor obtained in this precursor preparation step to form a bismuth-ruthenium oxide, and a nitric acid treatment step of immersing the bismuth-ruthenium oxide obtained by this calcination step in a nitric acid aqueous solution.

In some aspects and embodiments, the present application provides a wide range of porous 1-D polymeric graphitic carbon-nitride materials that are atomically doped with binary metals in different morphologies. In some embodiments, the graphitic carbon-nitride materials can be prepared with high mass production from inexpensive and natural abundant precursors. In some embodiments, the materials were used successfully for the oxidation of CO to CO.sub.2 under ambient reaction temperature in addition to the reduction of CO.sub.2 into hydrocarbons. In some embodiments, the materials can be used for practical and large-scale gas conversion for household or industrial applications.

Disclosed herein are a calcium salts-supported metal catalyst, a method for preparing the same, and a method for the hydrodeoxygenation reaction of oxygenates using the same. The catalyst, in which a metal catalyst is supported on a carrier of a calcium salt, for example, calcium carbonate, has the effect of increasing the efficiency of hydrodeoxygenation reaction of oxygenates.

Disclosed is a method of preparing a high-performance zeolite catalyst for reducing nitrogen oxide emissions, and more particularly a technique for preparing a zeolite catalyst, suitable for use in effectively removing nitrogen oxide (NOx), among exhaust gases emitted from vehicle internal combustion engines through selective catalytic reduction (SCR), thereby exhibiting high efficiency, high chemical stability and high thermal durability upon SCR using the prepared catalyst.

Provided are an air-cleaning device and method for reducing harmful gas including ethylene and harmful microorganisms, and an air-cleaning system including the air-cleaning device.

Provided is a catalytic activity recovery method of a manganese oxide catalyst, an air-cleaning device using the same, air-cleaning system including the air-cleaning device, and an operation method of air-cleaning device by using the manganese oxide catalyst. The catalytic activity recovery method of a manganese oxide catalyst includes recovering the initial activity of a manganese Ni oxide catalyst by heating a manganese oxide catalyst which has been used to decompose ozone and of which activity is thus reduced by 10% or more compared to the initial ozone decomposition efficiency thereof, at the temperature of 80 C. to 250 C., so as to recover an ozone decomposition efficiency represented by Equation 1 to 90% or more of the initial ozone decomposition efficiency: Equation 1 Ozone decomposition efficiency (%)=[1(concentration of ozone flowing out of the reactor)/(concentration of ozone flowing into the reactor)]100

Methods of preparing Pt/SrTiO.sub.3 photocatalysts comprising strontium titanate nanoparticles and platinum doped on a surface of the strontium titanate nanoparticles are described. Processes of oxidizing cycloalkanes to cycloalkanols and/or cycloalkanones by employing the Pt/SrTiO.sub.3 photocatalysts are specified. A method for recycling the photocatalyst is also provided.

Provided is an inorganic oxide containing Al, Ce and Zr as constituent elements and having a ratio of emission intensity I.sub.A at 420 nm and emission intensity I.sub.B at 470 nm (I.sub.B/I.sub.A) of not more than 1.65 in an emission spectrum obtained when a light at wavelength 200 nm is irradiated.

Provided are the following: a mixture of visible light-responsive photocatalytic titanium oxide fine particles which can conveniently produce a photocatalyst thin film that exhibits photocatalyst activity even with only visible light (400-800 nm) and that exhibits high transparency; a dispersion liquid of the fine particles; a method for producing the dispersion liquid; a photocatalyst thin film; and a member having the photocatalyst thin film on a surface thereof. The mixture of visible light-responsive photocatalytic titanium oxide fine particles is characterized by containing two kinds of titanium dioxide fine particles: first titanium oxide fine particles, in which a tin component and a transition metal component (excluding an iron group element component) that increases visible light response properties form a solid solution, and second titanium oxide fine particles, in which an iron group element component and a chromium group element component form a solid solution.