A template-assisted method for the synthesis of 2D nanosheets comprises growing a 2D material on the surface of a nanoparticle substrate that acts as a template for nanosheet growth. The 2D nanosheets may then be released from the template surface, e.g. via chemical intercalation and exfoliation, purified, and the templates may be reused.

A nanostructure is provided that in one embodiment includes a cluster of cylindrical bodies. Each of the cylindrical bodies in the cluster are substantially aligned with one another so that their lengths are substantially parallel. The composition of the cylindrical bodies include tungsten (W) and sulfur (S), and each of the cylindrical bodies has a geometry with at least one dimension that is in the nanoscale. Each cluster of cylindrical bodies may have a width dimension ranging from 0.2 microns to 5.0 microns, and a length greater than 5.0 microns. In some embodiments, the cylindrical bodies are composed of tungsten disulfide (WS2). In another embodiment the nanolog is a particle comprised of external concentric disulfide layers which encloses internal disulfide folds and regions of oxide. Proportions between disulfide and oxide can be tailored by thermal treatment and/or extent of initial synthesis reaction.

A nanostructure is provided that in one embodiment includes a cluster of cylindrical bodies. Each of the cylindrical bodies in the cluster are substantially aligned with one another so that their lengths are substantially parallel. The composition of the cylindrical bodies include tungsten (W) and sulfur (S), and each of the cylindrical bodies has a geometry with at least one dimension that is in the nanoscale. Each cluster of cylindrical bodies may have a width dimension ranging from 0.2 microns to 5.0 microns, and a length greater than 5.0 microns. In some embodiments, the cylindrical bodies are composed of tungsten disulfide (WS2). In another embodiment the nanolog is a particle comprised of external concentric disulfide layers which encloses internal disulfide folds and regions of oxide. Proportions between disulfide and oxide can be tailored by thermal treatment and/or extent of initial synthesis reaction.

Present subject matter provides a semiconductor nanocrystal comprises a core and a shell. The core is fabricated from a first semiconductor. The shell is fabricated from a second semiconductor. The optical cross section of the semiconductor nanocrystal is in a range of 10.sup.17 cm.sup.2-10.sup.12 cm.sup.2 in a 2-3 eV region. The core is less than 2 nanometers from an outer surface of the shell in at least one region of the semiconductor nanocrystal. Present subject matter also provides method for preparation of the semiconductor nanocrystals and method for photosynthesis of organic compounds.

A method for oxidative desulfurization of liquid hydrocarbon fuels is disclosed. The method includes contacting a liquid fuel with a quantum dot hybrid catalyst including metal sulfide quantum dots intercalated over graphene oxide layers in a reactor vessel, heating the reactor vessel to a temperature between 25 C. and 200 C., and reducing sulfur content of the liquid fuel with a sulfur reduction amount of more than 95% wt. Reducing the sulfur content of the liquid fuel with the sulfur reduction amount of more than 95% wt. includes producing sulfone and sulfoxide compounds by oxidizing the liquid fuel with ozone gas in the presence of the quantum dot hybrid catalyst at the temperature between 25 C. and 200 C., and separating the sulfone and sulfoxide compounds from the liquid fuel by extracting the sulfone and sulfoxide with an extraction solvent.

A method for oxidative desulfurization of liquid hydrocarbon fuels is disclosed. The method includes contacting a liquid fuel with a quantum dot hybrid catalyst including metal sulfide quantum dots intercalated over graphene oxide layers in a reactor vessel, heating the reactor vessel to a temperature between 25 C. and 200 C., and reducing sulfur content of the liquid fuel with a sulfur reduction amount of more than 95% wt. Reducing the sulfur content of the liquid fuel with the sulfur reduction amount of more than 95% wt. includes producing sulfone and sulfoxide compounds by oxidizing the liquid fuel with ozone gas in the presence of the quantum dot hybrid catalyst at the temperature between 25 C. and 200 C., and separating the sulfone and sulfoxide compounds from the liquid fuel by extracting the sulfone and sulfoxide with an extraction solvent.

A template-assisted method for the synthesis of 2D nanosheets comprises growing a 2D material on the surface of a nanoparticle substrate that acts as a template for nanosheet growth. The 2D nanosheets may then be released from the template surface, e.g. via chemical intercalation and exfoliation, purified, and the templates may be reused.

A template-assisted method for the synthesis of 2D nanosheets comprises growing a 2D material on the surface of a nanoparticle substrate that acts as a template for nanosheet growth. The 2D nanosheets may then be released from the template surface, e.g. via chemical intercalation and exfoliation, purified, and the templates may be reused.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650 C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

The present invention relates to an oxygen reduction catalyst, an electrode, a membrane electrode assembly, and a fuel cell, and the oxygen reduction catalyst is an oxygen reduction catalyst containing substituted CoS.sub.2, in which the substituted CoS.sub.2 has a cubic crystal structure, the oxygen reduction catalyst contains the substituted CoS.sub.2 within 0.83 nm from the surface thereof, and the substituted CoS.sub.2 has at least one substitutional atom selected from the group consisting of Cr, Mo, Mn, Tc, Re, Rh, Cu, and Ag in some of Co atom sites.