The present invention concerns a method for the preparation of metal oxide hollow nanoparticles comprising the steps of: providing an aqueous suspension of nanoparticles of an oxide of a first element having at least two oxidation states coupled with a substrate; placing in contact the aqueous suspension with an aqueous solution of a salt of a second element having at least two oxidation states having a standard reduction potential lower than the standard reduction potential of said first transition metal to obtain hollow nanoparticles.

The present invention provides magnetic macroporous polymeric hybrid scaffolds for supporting and enhancing the effectiveness of bionanocatalysts (BNC). The novel scaffolds comprise cross-linked water-insoluble polymers and an approximately uniform distribution of embedded magnetic microparticles (MMP). The cross-linked polymer comprises polyvinyl alcohol (PVA) and optionally additional polymeric materials. The scaffolds may take any shape by using a cast during preparation of the scaffolds. Alternatively, the scaffolds may be ground to microparticles for use in biocatalytic reactions. Alternatively, the scaffolds may be shaped as beads for use in biocatalyst reactions. Methods for preparing and using the scaffolds are also provided.

The invention provides a process for treating waste water from an industrial process for producing propylene oxide, which process comprises subjecting the waste water to a catalytic wet oxidation treatment in the presence of a catalyst comprising metal nanoparticles-doped porous carbon beads.

The present invention relates to a new method for creating nanopores in single layer molybdenum disulfide (MoS.sub.2) nanosheets (NSs) by the electrospray deposition (ESD) of silver ions on a water suspension of the former. Electrospray deposited silver ions react with the MoS.sub.2 NSs at the liquid-air interface resulting in Ag.sub.2S nanoparticles (NPs) which goes into the solution leaving the NSs with holes of 3-5 nm diameter. Specific reaction with the S of MoS.sub.2 NSs leads to Mo-rich edges. Such Mo-rich defects are highly efficient for the generation of active oxygen species such as H.sub.2O.sub.2, under visible light, which causes efficient disinfection of water. The holey MoS.sub.2 NSs shows 10.sup.5 times higher efficiency in disinfection compared to normal MoS.sub.2 NSs. Developed a conceptual prototype and tested with multiple bacterial strains and a viral strain, demonstrating the utility of the method for practical applications.

The invention relates to a method of preparing titanium dioxide-coated nanostars. Titanium precursors are hydrolyzed into crystalline TiO.sub.2 polymorphs at low temperatures, allowing the delicate morphology of the nanostars to be preserved while maintaining their desirable photocatalytic properties.

A mesoporous metal doped cerium oxide catalyst is provided. The catalyst can contain nanotextured cerium oxide (CeO.sub.2) which can be utilized for hydrogen production or reformate gas purification in a water gas shift reaction. The catalyst may be advantageously used to remove CO from a gas containing CO. The catalyst may also be incorporated into a fuel processor.

Disclosed are catalysts comprised of platinum and gold. The catalysts are generally useful for the selective oxidation of compositions comprised of a primary alcohol group and at least one secondary alcohol group wherein at least the primary alcohol group is converted to a carboxyl group. More particularly, the catalysts are supported catalysts including particles comprising gold and particles comprising platinum, wherein the molar ratio of platinum to gold is in the range of about 100:1 to about 1:4, the platinum is essentially present as Pt(0) and the platinum-containing particles are of a size in the range of about 2 to about 50 nm. Also disclosed are methods for the oxidative chemocatalytic conversion of carbohydrates to carboxylic acids or derivatives thereof. Additionally, methods are disclosed for the selective oxidation of glucose to glucaric acid or derivatives thereof using catalysts comprising platinum and gold. Further, methods are disclosed for the production of such catalysts.

A method for synthesizing a nano-sized mesoporous zeolite composition, comprising: mixing silica, a source of aluminum, and tetraethylammonium hydroxide to form an aluminosilicate fluid gel; drying the aluminosilicate fluid gel to form a dried gel mixture; subjecting the dried gel mixture to hydrothermal treatment to produce a zeolite precursor; adding cetyltrimethylammonium bromide (CTAB) to the zeolite precursor to form a templated mixture; subjecting the templated mixture to hydrothermal treatment to prepare a CTAB-templated zeolite.

The synthesis of silver nanoparticles (AgNPs)/meso-porous silicon (PSi) nanocomposite and its effective use as efficient chemical sensor and photocatalyst are described. The PSi was prepared via a simple stain etching of Si microparticles in HF/HNO.sub.3 aqueous solution, followed by the deposition of AgNPs onto stain etched PSi by the immersion plating technique. The resultant nanocomposite is used successfully for (i) enhanced electro-oxidation and quantification of ascorbic acid (AA) on modified glassy carbon electrode and (ii) for the photo-reduction of hexavalent chromium Cr(VI) to trivalent Cr(III) under direct visible light irradiation in the presence of citric acid.

A hydrocarbon adsorbent, according to one embodiment of the present invention, comprises a copper-containing ZSM-5 zeolite, wherein a Si/Al molar ratio of the ZSM-5 zeolite may be 11.5 to 40, and the amount of the copper included is 1 wt % to 10 wt %.