Abstract: Nanoparticles include or consist essentially of (i) a core that itself includes or consists essentially of a first material, and (ii) a layer including or consisting essentially of a second material. In various embodiments, one of the first and second materials is a semiconductor material incorporating ions from group 13 and group 15 of the periodic table, and the other of the first and second materials is a metal oxide material incorporating metal ions selected from any one of groups 1 to 12, 14 and 15 of the periodic table. In other embodiments, one of the first and second materials is a semiconductor material, and the other of the first and second materials is an oxide of a metal selected from any one of groups 3 to 10 of the periodic table. Methods for preparing such nanoparticles are also described.

Abstract: A lighting fixture for promoting the development of animals comprises a backlight, such as an LED or an array of LEDs, and a series of one or more retractable, rotatable or interchangeable lenses comprising quantum dots, such that the color and/or color temperature of the light emitted by the lighting fixture can be altered and optimized during animal development. A lighting fixture adapted for use on an aquarium may be in the form factor of a standard fluorescent tube and comprise one or more LEDs and a quantum dot-containing film for down-converting at least a portion of the light emitted by the LEDs so as to provide optimum wavelengths for photosynthesis by aquarium plants while simultaneously providing attractive display lighting for the aquarium fish.

Abstract: Light-emitting materials are made from a porous light-emitting semiconductor having quantum dots (QDs) disposed within the pores. According to some embodiments, the QDs have diameters that are essentially equal in size to the width of the pores. The QDs are formed in the pores by exposing the porous semiconductor to gaseous QD precursor compounds, which react within the pores to yield QDs. According to certain embodiments, the pore size limits the size of the QDs produced by the gas-phase reactions. The QDs absorb light emitted by the light-emitting semiconductor material and reemit light at a longer wavelength than the absorbed light, thereby “down-converting” light from the semiconductor material.

Abstract: A light emitting layer including a plurality of light emitting particles embedded within a host matrix material. Each of said light emitting particles includes a population of semiconductor nanoparticles embedded within a polymeric encapsulation medium. A method of fabricating a light emitting layer comprising a plurality of light emitting particles embedded within a host matrix material, each of said light emitting particles comprising a population of semiconductor nanoparticles embedded within a polymeric encapsulation medium. The method comprises providing a dispersion containing said light emitting particles, depositing said dispersion to form a film, and processing said film to produce said light emitting layer.

Abstract: Light-emitting materials are made from a porous light-emitting semiconductor having quantum dots (QDs) disposed within the pores. According to some embodiments, the QDs have diameters that are essentially equal in size to the width of the pores. The QDs are formed in the pores by exposing the porous semiconductor to gaseous QD precursor compounds, which react within the pores to yield QDs. According to certain embodiments, the pore size limits the size of the QDs produced by the gas-phase reactions. The QDs absorb light emitted by the light-emitting semiconductor material and reemit light at a longer wavelength than the absorbed light, thereby “down-converting” light from the semiconductor material.

Abstract: A method of producing nanoparticles comprises effecting conversion of a nanoparticle precursor composition to the material of the nanoparticles. The precursor composition comprises a first precursor species containing a first ion to be incorporated into the growing nanoparticles and a separate second precursor species containing a second ion to be incorporated into the growing nanoparticles. The conversion is effected in the presence of a molecular cluster compound under conditions permitting seeding and growth of the nanoparticles.

Abstract: A method of producing nanoparticles comprises effecting conversion of a molecular cluster compound to the material of the nanoparticles. The molecular cluster compound comprises a first ion and a second ion to be incorporated into the growing nanoparticles. The conversion can be effected in the presence of a second molecular cluster compound comprising a third ion and a fourth ion to be incorporated into the growing nanoparticles, under conditions permitting seeding and growth of the nanoparticles via consumption of a first molecular cluster compound.

Abstract: Coated beads made of a primary matrix material and containing a population of quantum dot nanoparticles. Each bead has a multi-layer surface coating. The layers can be two or more distinct surface coating materials. The surface coating materials may be inorganic materials and/or polymeric materials. A method of preparing such particles is also described. The coated beads are useful for composite materials for applications such as light-emitting devices.

Abstract: An illuminated sign has a primary light source in spaced apart relation to a transparent or translucent substrate having quantum dot phosphors printed or coated thereon. The primary light source may be a blue LED, a white LED or an LED having a significant portion of its emission in the ultraviolet region of the spectrum. The LED may be a backlight for the transparent or translucent substrate and/or an edge light, a down light or an up light.

Abstract: The present invention relates to a primary particle comprised of a primary matrix material containing a population of semiconductor nanoparticles, wherein each primary particle further comprises an additive to enhance the physical, chemical and/or photo-stability of the semiconductor nanoparticles. A method of preparing such particles is described. Composite materials and light emitting devices incorporating such primary particles are also described.

Abstract: Embodiments of the present invention relate to a formulation for use in the fabrication of a light-emitting device, the formulation including a population of semiconductor nanoparticles incorporated into a plurality of discrete microbeads comprising an optically transparent medium, the nanoparticle-containing medium being embedded in a host light-emitting diode encapsulation medium. A method of preparing such a formulation is described. There is further provided a light-emitting device including a primary light source in optical communication with such a formulation and a method of fabricating the same.

Abstract: Nanoparticles containing IUPAC group 11 ions, group 13 ions and sulfur ions are synthesized by adding metal salts and an alkanethiol in an organic solvent and promoting the reaction by applying heat. Nanoparticles are formed at temperatures as low as 200° C. The nanoparticles may be thermally annealed for a certain amount of time at a temperature lower than the reaction temperature (usually ˜40° C. lower) to improve the topology and narrow the size distribution. After the reaction is complete, the nanoparticles may be isolated by the addition of a non-solvent and re-dispersed in organic solvents including toluene, chloroform and hexane to form a nanoparticle ink. Additives may be incorporated in the reaction solution to tailor the final ink viscosity.

Abstract: Embodiments of the present invention relate to a formulation for use in the fabrication of a light-emitting device, the formulation including a population of semiconductor nanoparticles incorporated into a plurality of discrete microbeads comprising an optically transparent medium, the nanoparticle-containing medium being embedded in a host light-emitting diode encapsulation medium. A method of preparing such a formulation is described. There is further provided a light-emitting device including a primary light source in optical communication with such a formulation and a method of fabricating the same.

Abstract: Disclosed herein are coated beads made of a primary matrix material and containing a population of quantum dot nanoparticles. Each bead has a multi-layer surface coating. The layers can be two or more distinct surface coating materials. The surface coating materials may be inorganic materials and/or polymeric materials. A method of preparing such particles is also described. The coated beads are useful for composite materials for applications such as light-emitting devices.

Abstract: A method of preparing Group XIII selenide nanoparticles comprises reacting a Group XIII ion source with a selenol compound. The nanoparticles have an MxSey Semiconductor core (where M is In or Ga) and an organic capping ligand attached to the core via a carbon-selenium bond. The selenol provides a source of selenium for incorporation into the semiconductor core and also provides the organic capping ligand. The nanoparticles are particularly suitable for solution-based methods of preparing semiconductor films.

Abstract: Materials and methods for preparing Cu2XSnY4 nanoparticles, wherein X is Zn, Cd, Hg, Ni, Co, Mn or Fe and Y is S or Se, (CXTY) are disclosed herein. The nanoparticles can be used to make layers for use in thin film photovoltaic (PV) cells. The CXTY materials are prepared by a colloidal synthesis in the presence of labile organo-chalcogens. The organo-chalcogens serves as both a chalcogen source for the nanoparticles and as a capping ligand for the nanoparticles.

Abstract: A method of heat transfer printing using quantum dots is described. The method can be used to form an image using quantum dots on a substrate that is not easily printed using conventional printing techniques. Also described is a quantum dot ink formulation for heat transfer printing. The methods and materials can be used for anti-counterfeiting applications.

Abstract: Materials and methods for preparing Cu2ZnSnS4 (CZTS) layers for use in thin film photovoltaic (PV) cells are disclosed herein. The CZTS materials are nanoparticles prepared by a colloidal synthesis in the presence of a labile organothiol. The organothiol serves as both a sulphur source and as a capping ligand for the nanoparticles.

Abstract: A method of preparing Group XIII selenide nanoparticles comprises reacting a Group XIII ion source with a selenol compound. The nanoparticles have an MxSey semiconductor core (where M is In or Ga) and an organic capping ligand attached to the core via a carbon-selenium bond. The selenol provides a source of selenium for incorporation into the semiconductor core and also provides the organic capping ligand. The nanoparticles are particularly suitable for solution-based methods of preparing semiconductor films.

Abstract: A method of producing nanoparticles comprises effecting conversion of a nanoparticle precursor composition to the material of the nanoparticles. The precursor composition comprises a first precursor species containing a first ion to be incorporated into the growing nanoparticles and a separate second precursor species containing a second ion to be incorporated into the growing nanoparticles. The conversion is effected in the presence of a molecular cluster compound under conditions permitting seeding and growth of the nanoparticles.