Methods for making a multilevel core-shell structure having a core/graphene-based shell structure are described. A method for making a core/graphene-based shell structure can include obtaining a composition that includes core nano- or microstructures and graphene-based structures having at least a portion of a surface coated with a curable organic material, where the core nano- or microstructures and graphene-based structures are dispersed throughout the composition and subjecting the composition to conditions that cure the organic material and allow the graphene-based structures to self-assemble around the core nano- or microstructures to produce a core/graphene-based shell structure that has a graphene-based shell encompassing a core nano- or microstructure.

Methods for making a multilevel core-shell structure having a core/graphene-based shell structure are described. A method for making a core/graphene-based shell structure can include obtaining a composition that includes core nano- or microstructures and graphene-based structures having at least a portion of a surface coated with a curable organic material, where the core nano- or microstructures and graphene-based structures are dispersed throughout the composition and subjecting the composition to conditions that cure the organic material and allow the graphene-based structures to self-assemble around the core nano- or microstructures to produce a core/graphene-based shell structure that has a graphene-based shell encompassing a core nano- or microstructure.

A process for producing a polyetheramine by reacting a polyether alcohol, previously synthesized in the presence of a basic potassium or sodium compound as catalyst, with ammonia in the presence of hydrogen and a catalyst in one reactor or a plurality of reactors, wherein the employed polyether alcohol when previously synthesized in the presence of a basic potassium compound as catalyst has a content of potassium ions of less than 50 wppm and when previously synthesized in the presence of a basic sodium compound as catalyst has a content of sodium ions of less than 50 wppm.

A process for producing a polyetheramine by reacting a polyether alcohol, previously synthesized in the presence of a basic potassium or sodium compound as catalyst, with ammonia in the presence of hydrogen and a catalyst in one reactor or a plurality of reactors, wherein the employed polyether alcohol when previously synthesized in the presence of a basic potassium compound as catalyst has a content of potassium ions of less than 50 wppm and when previously synthesized in the presence of a basic sodium compound as catalyst has a content of sodium ions of less than 50 wppm.

An organic nanofiber includes a fiber body containing multiple inorganic oxide particles selected from polycrystalline titanium dioxide particles and polycrystalline tin(IV) oxide particles, and having a particle size ranging from 15 to 75 nm. A method for manufacturing the inorganic nanofibers, including: mixing a metal precursor, an organic polymer and a solvent to obtain a solution, the metal precursor being a titanium-containing precursor or a tin-containing precursor; electrospinning the solution at a relative humidity ranging from 50 to 60% to form multiple nanofibers; and annealing the nanofibers at a temperature ranging from 600 to 800° C. to obtain multiple inorganic nanofibers.

An organic nanofiber includes a fiber body containing multiple inorganic oxide particles selected from polycrystalline titanium dioxide particles and polycrystalline tin(IV) oxide particles, and having a particle size ranging from 15 to 75 nm. A method for manufacturing the inorganic nanofibers, including: mixing a metal precursor, an organic polymer and a solvent to obtain a solution, the metal precursor being a titanium-containing precursor or a tin-containing precursor; electrospinning the solution at a relative humidity ranging from 50 to 60% to form multiple nanofibers; and annealing the nanofibers at a temperature ranging from 600 to 800° C. to obtain multiple inorganic nanofibers.

Provided is a photocatalytic composition comprising zinc (Zn) doped titanium dioxide (TiO.sub.2) nanoparticles, wherein the ratio of titanium dioxide nanoparticles to zinc is from about 5 to about 150. The photocatalytic composition absorbs electromagnetic radiation in a wavelength range from about 200 nm to about 500 nm, and the absorbance of light of wavelengths longer than about 450 nm is less than 50% the absorbance of light of wavelengths shorter than about 350 nm.

The present invention relates to a methane combustion catalyst including platinum and iridium supported on a tin oxide carrier for combusting methane in a combustion exhaust gas containing sulfur oxide. In the methane combustion catalyst, a ratio R.sub.TO of platinum oxides to metal platinum is 8.00 or more, wherein the ratio R.sub.TO is based on existence percentages of the metal platinum (Pt) and the platinum oxides (PtO and PtO.sub.2) obtained from a platinum 4f spectrum analyzed and measured by X-ray photoelectron spectroscopy (XPS) and calculated in accordance with the following expression. In the following expression, R.sub.Pt is an existence percentage of the metal platinum (Pt), R.sub.Pto is an existence percentage of PtO, and R.sub.Pto2 is an existence percentage of PtO.sub.2.

R.sub.TO=(R.sub.PtO+R.sub.PtO2)/R.sub.Pt  [Expression 1]

The present invention relates to a methane combustion catalyst including platinum and iridium supported on a tin oxide carrier for combusting methane in a combustion exhaust gas containing sulfur oxide. In the methane combustion catalyst, a ratio R.sub.TO of platinum oxides to metal platinum is 8.00 or more, wherein the ratio R.sub.TO is based on existence percentages of the metal platinum (Pt) and the platinum oxides (PtO and PtO.sub.2) obtained from a platinum 4f spectrum analyzed and measured by X-ray photoelectron spectroscopy (XPS) and calculated in accordance with the following expression. In the following expression, R.sub.Pt is an existence percentage of the metal platinum (Pt), R.sub.Pto is an existence percentage of PtO, and R.sub.Pto2 is an existence percentage of PtO.sub.2.

R.sub.TO=(R.sub.PtO+R.sub.PtO2)/R.sub.Pt  [Expression 1]

Disclosed herein are base metal catalyst devices for removing ozone, volatile organic compounds, and other pollutants from an air flow stream. A catalyst device includes a housing, a solid substrate disposed within the housing, and a catalyst layer disposed on the substrate. The catalyst layer includes a first base metal catalyst at a first mass percent, a second base metal catalyst at a second mass percent, and a support material impregnated with at least one of the first base metal catalyst or the second base metal catalyst. The preferred catalyst composition is a combination of manganese oxide and copper oxide.