The present invention disclosed an improved process for the preparation of bimetallic core-shell nanoparticles by using facile aqueous phase synthesis strategy and their application in catalysis such as selective hydrogenation of alkynes into alkenes or alkanes and CO hydrogenation to hydrocarbons.

A nanocomposite catalyst includes a support, a multiplicity of nanoscale metal oxide clusters coupled to the support, and one or more metal atoms coupled to each of the nanoscale metal oxide clusters. Fabricating a nanocomposite catalyst includes forming nanoscale metal oxide clusters including a first metal on a support, and depositing one or more metal atoms including a second metal on the nanoscale metal oxide clusters. The nanocomposite catalyst is suitable for catalyzing reactions such as CO oxidation, water-gas-shift, reforming of CO.sub.2 and methanol, and oxidation of natural gas.

A nanocomposite photocatalyst is provided. The nanocomposite photocatalyst contains a carbon nanomaterial made of amorphous carbon and graphitic carbon, metal oxide nanoparticles disposed on the carbon nanomaterial, and noble metal nanoparticles disposed on the metal oxide nanoparticles and/or the carbon nanomaterial. Also provided is a method of forming the nanocomposite photocatalyst and a method of photodegrading an organic pollutant in water using the nanocomposite photocatalyst and visible light irradiation.

Disclosed are a hollow mesoporous organic silica nano/microparticle having metal particles deposited thereon, and a method for preparing the same of the present disclosure. The method may prepare a spherical nanoparticle by coating a porous organic silica layer on an inorganic silica particle having the metal particles deposited thereon and via selective etching of the layer. In addition, two or more types of metals pre-synthesized together with a magnetic particle, or different shapes of metals may be deposited on the nanoparticle at a target concentration. Thus, the nano/microparticle may be used for a drug delivery matrix, a catalyst, and a photothermal effect.

Disclosed are a hollow mesoporous organic silica nano/microparticle having metal particles deposited thereon, and a method for preparing the same of the present disclosure. The method may prepare a spherical nanoparticle by coating a porous organic silica layer on an inorganic silica particle having the metal particles deposited thereon and via selective etching of the layer. In addition, two or more types of metals pre-synthesized together with a magnetic particle, or different shapes of metals may be deposited on the nanoparticle at a target concentration. Thus, the nano/microparticle may be used for a drug delivery matrix, a catalyst, and a photothermal effect.

An efficient green method for the synthesis of noble metal/transition metal oxide nanocomposite comprising reducing noble metal salt and a templating metal oxide is disclosed. The method is a one-step method comprises mixing coffee seed husk extract, a noble metal precursor, and a transition metal precursor; and filtering and drying the nanocomposite. The nanocomposite prepared by the method of the invention displays all the characteristics and biocidal activity of a composite prepared by traditional methods.

A method for preparing methyl methacrylate from methacrolein and methanol. The process comprises contacting in a reactor a mixture comprising methacrolein, methanol and oxygen with a heterogeneous catalyst comprising a support and a noble metal, wherein said catalyst has an average diameter of at least 200 microns, liquid and gaseous reactants flow downward in the reactor and wherein the continuous phase in the reactor is a gas which has no more than 7.5 mol % oxygen at reactor inlets.

A composition having a gadolinium-, samarium-, or lanthanum-substituted porous cerium oxide and copper or gold nanoparticles. The composition can be exposed to electromagnetic radiation to form reactive oxygen species in the composition to decompose organophosphonate compounds. The composition may be made by forming a mixture of a cerium salt; a gadolinium, samarium, or lanthanum salt; and an epoxide; forming gel from the mixture; and drying the gel to form an aerogel, a xerogel, or an ambigel. Copper or gold nanoparticles are added or formed at any point in the method.

A composition having a gadolinium-, samarium-, or lanthanum-substituted porous cerium oxide and copper or gold nanoparticles. The composition can be exposed to electromagnetic radiation to form reactive oxygen species in the composition to decompose organophosphonate compounds. The composition may be made by forming a mixture of a cerium salt; a gadolinium, samarium, or lanthanum salt; and an epoxide; forming gel from the mixture; and drying the gel to form an aerogel, a xerogel, or an ambigel. Copper or gold nanoparticles are added or formed at any point in the method.

The present invention provides materials for improving the ignition of gaseous reactants in metal catalyzed oxidation reactions comprising a metal catalyst gauze, preferably, a platinum/rhodium catalyst gauze, having in contact therewith, from 0.5 to 1.5 wt. %, based on the weight of the metal catalyst gauze, of one or more pieces of previously used metal catalyst gauze. Further, methods of making the metal catalyst materials comprise shaping the pieces of previously used metal catalyst gauze and placing them equidistant from each other in contact with or on the surface of the metal catalyst gauze. And methods of using the materials comprise feeding into the reactor a gas mixture of oxygen or air and one or more reactant gases, and igniting the gas mixture at the surface of one or more or all of the pieces of previously used metal catalyst.